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H. spelaa. Maximum (Wookey) : 1.1
i . . . . . . 10:41 045 0.59 0.75 0.36 0.75 0.98 1.65

1 0:35 0.55 0.68 0.93
H. spelea. Minimum (Wookey) :1: :
1 . . . . . .

. 10.35 0.67 0.96 1.5 2 . . .

0.53 0.79 10.9 .

. 10.3

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XI. SKETCH OF THE PRIMARY GROUPS OF BATRACHIA SALIENTIA.

By Edward D. Cope, of the Academy of Natural Sciences, Philadelphia, U. S. A.; C. M. Z. S. L.

Tre peculiarities of their osseous structure appear to point out among the families of the Batrachia salientia three series. First, those characterized by an absence of teeth and manubrium sterni, where the diapophysis of the sacrum is dilated, and the stérnum with or without cartilaginous arches. Secondly, those having teeth, the coracoid and epicoracoid bones divergent and connected by a longitudinally placed cartilaginous arch,* that of the one side overlapping that of the other; the sacral diapophysis being either dilated or cylindrical, and the manubrium present or absent. Thirdly, those haring teeth, the sacral diapophysis cylindrical, and a sternum of the following structure. The axes of the coracoid and epicoracoid are parallel, not divergent, their distal extremities separated only by interposed articular cartilage, and that of the epicoracoid resting upon that of the coracoid, which is much dilated: there are therefore do arciform cartilages. There is always a bony manubrium, and usually an osseous styliform xiphisternal piece.

These series may be called the Bufoniformia, the Arcifera, and the Raniformia. The first is extensively developed in the Neotropical, the Æthiopian, and Palæotropical regions; many species occur in the Nearctic district, a small number in the Palæarctic, and but three in the Australian. The second is found in all the regions of the globe except the Æthiopian, but is relatively much most developed in the Australian and Neotropical faune; in the Palæotropical but four or five species occur. The Raniformia, on the contrary, are not found in Australia, are represented by but one species in South America, are well represented (relatively) in the Noarctic and Palæarctic regions, abound in the Æthiopian, but are most numerous in the Palæotropical.

In each of these series or suborders we find types adapted for

• Plainly homologous with those connecting the coracoids and epicoracoids of the Lacertilia. They are homologized by M. Dugès with the clavicles; and the bones asually so called in the Batrachia salientia he terms acromials. A superficial view favours the opinion that the latter are rather epicoracoide, and that the clavicles of the Lacertilia have no homologue among the Frogs.

N.H.R.-1865.

A

burrowing, others for an aquatic life; some are entirely terrestrial, and some are constructed for maintaining their position upon the leaves and branches of trees. But the different adaptive modification so graduate into each other on one hand, while similar ones are 80 constantly separate on the other, different structures frequently serving the same purpose,* that we are compelled to believe that a different idea pervades the scheme; and that, although adaptive modifications undoubtedly distinguish many generic and such subordinate types, the direction of their series is in accordance with another law which is not explained. This is the case, it will be seen, within the more definitely restricted series, the families.

In addition to the many species constituting the three suborders above-mentioned, there are known three living and perhaps as many extinct ones characterized by an extension of the pterygoid bones so as to enclose the cava tympani and tubæ Eustachii, causing the latter to present a single united ostium pharyngium. The living species have at the same time no tongue. The genera Pipa, Dactylethra, and Palæobatrachus are alluded to. The vertebræ in these animals are opisthocælian, as in the Salamanders, and their sternum of the arciferous type.

constituting a distinct suborder; but it is possible that Palæobatrachus and Dactylethra may come to be looked upon as extremes of the series of Arcifera, succeeding the family Asterophrydide of the latter. The peculiar vertebre without ribs and the simply articulated coccyx are points of resemblance which do not occur elsewhere. In Pipa the relations of the fronto-parietal, ethmoid and prefrontal bones, also the sternum, find a close parallel in the Rhinophrynide, which, with the absence of teeth, suggest that it may be the most divergent type of the Bufoniform suborder.

AGLOSSA.

PIPIDE. No ribs; simple coccyx attached to a single condyle. Coracoid and epicoracoid divergent, their connecting arches not overlapping. No manubrium. Fronto-parietal completely ossified ; prefrontals

Tide Professor Owen, in Trans. Zool. Soc. vol. v, p. 91, line 21.

separate. Teeth none; sacral diapophyses dilated. Terminal phalanges acute, simple. External metatarsals separated by a web.

The Neotropical genus Pipa has the atlas confluent with the second vertebra, so that there are but seven anterior to the sacrum. There are distinct nasal bones, and the median septum of the ethmoid is partially ossified. The prefrontals are completely in contact with each other and with the fronto-parietal.

DACTYLETIRIDE. No ribs: os ilium attached to the ninth vertebra only. Coracoids and epicoracoids well separated from those of the opposite side. Fronto-parietal strongly ossified, overhanging the confluent prefrontals. Teeth present; sacral diapophyses dilated. Terminal phalanges acute, simple. External metatarsals separated by a web.

One genus Dactylethra, in the Regio Æthiopica. In this the interorbital ethmoid plate, though long, is not produced anteriorly, and is entirely concealed by the fronto-parietal. The prefrontal does not always extend to it. The first two vertebræ are separate, but the sacral and coccyx confluent. There are ossa nasalia above the nares.

PALÆOBATRACHIDÆ. No ribs: os ilium attached to the diapophyses of the confluent ninth, eighth, and seventh vertebræ, which form a disc; coccyx attached by a simple glenoid cavity. Fronto-parietal strongly ossified, not produced further than the separate prefrontals. External metatarsals probably separated by a web.

The genus Palæobatrachus, Tsch., represented by several species in the miocene of Germany. The superior plate of the ethmoid was concealed; and the atlas confluent with the first vertebra, leaving but six between the occiput and sacrum.

Von Meyer states* that, of a great number of specimens of P. diluvianus which he examined, but one exhibited the complete developmental stage, as indicated by the complete fusion of the sacral diapophyses, which is certainly a remarkable circumstance. Such an one preserved in the British Museum has opisthocælian vertebræ. Von Meyer describes the vertebræ of P. giganteus as procælian, while some of them are figured as opisthocælian. It remains there

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ore a question of interest whether any species of this family possesses the ordinary Batrachian type of vertebræ.

BUFONIFORMIA. No species of this suborder has articulated ribs or opisthocælian vertebræ, nor a distinct web between the external metatarsal bones. In one genus only are the sacral diapophyses cylindrical. The families are the Rhinophrynida, Engystomida, Brachymerida, Bufomide, and Dendrobatide.

RHINOPIRYNIDÆ. Ethmoid septal walls ossified to the end of the muzzle, and separating the prefrontals; its superior plate covered by the completely ossified fronto-parietale. Fronto-nasalia well developed, entirely in contact with fronto-parietalia, separated by a median point of the latter and by the ethmoid septum. No os pterygoideum or pterygoid wing of ectopterygoid: the latter straight, with a short maxillary suture. Sacral diapophysis dilated. Coracoid and epicoracoid divergent, connected by a narrow single cartilage; the former not dilated, in contact with, or slightly separated from, that of the opposite side. Tongue bound or retractile posteriorly. Ear imperfectly developed.

Rhinophrynus and Hemisus represent this form in Mexico and Africa respectively. In the latter genus the coracoidii are in contact, and there is a strong manubrium: the posterior free border of the tongue may be drawn into a transverse slit by a flabelliform retractor muscle. This slit is beneath the free portion of the tongue when it is extended. * In both genera there are nine vertebræ (inclusive of sacral) and a coccyx attached to two condyles.

ENGYSTOMID Æ. Ethmoid septal walls cartilaginous ; the interorbital portion of the superior plate usually covered by the completely ossified frontoparietals. No pterygoidium. Sacral diapophyses dilated. Coracoids dilated, always in contact with each other, also with the epicoracoids when present (with one exception), and always without árciform cartilages. Tongue free, not retractile posteriorly.

There are two types in this family. In the first the o. prefrontalia

This I first observed in a specimen of Hemisus guineensis preserved in the muscum of Professor Geheimrath Hyrtl, in Vienna, to whom I am under many obligations for opportunities of studying valuable specimens and preparations.

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