234 BULLETIN 34, UNITED STATES NATIONAL MUSEUM. 



Fi'oiH the external edge of each of these four cartilages the cerato- 

 braiicbials radiate. The fourth or posterior is frequently confluent 

 with its hyobranchial. (Plate 51, fig. 1.) With the completion of the 

 metamorphosis the basi- and hyobrauchials fuse into a single piece, 

 and the ceratobrauchials unite with the same plate, excepting the 

 fourth, which, becoming ossified, forms the only true bone of the re- 

 gion. In some types the ossification becomes more extensive, as in 

 Cyclorhamphus ; (Plate 76, fig. 10.) Sometiaies the third ceratobran- 

 chial is ossified, as in Alytes [1. c, fig. 2) and Hemisus [1. c, fig. 18). 



The digits of the Salientia are apparently four anteriorly and five pos- 

 teriorly ; there is generally a rudimental digit, in addition, on the inner, 

 side of each foot. The thumb is especially well developed in the Hylid 

 genus, Hypsiboas Wagl.; (Plate 72, fig. 20.) The inner digit of the pos- 

 terior foot, or the internal hallux, as it is called, has three elements in 

 some of the Eanas (see Plate 65, Bana catehesiana), while in other forms 

 the digit is principally represented b^^ a large flat phalange. This is 

 called the spur or metatarsal tubercle in works on the subject, and it is 

 sometimes incorrectly referred to the tarsus. 



The carpus of the Salientia has but two proximal elements, the inter- 

 medium not being distinct. There is a large centrale, which forms part 

 of the inner border of the palm. The order is further characterized (ex- 

 cept in the Discoglossid^e and the Agiossa, q, v.) by the fusion of the 

 fourth and fifth carpalia into a single element, the unciforme. 'The 

 other three carpalia are distinct, and the first is frequently displaced 

 to form the base for the metacarpus of the thumb. The large size of the 

 astragalus and calcaneum have been already referred to, The tarsus is 

 further peculiar in the absence of intermedium and centrale and the 

 absence of tarsalia, except a rudiment or two near the inner part of 

 their usual position. (Plate 73.)* 



INTEGUMENT. 



The slight attachment of the integument to the muscles is a well- 

 known feature of the Batrachia Salientia. The manner of their attach- 

 ment presents many varieties in the different groups. It is as follows : 

 A transverse partition of connective tissue holds the integument along 

 the acromials and another along the coracoids; a longitudinal band on 

 each side of the back (frequently marked externally by a glandular fold) 

 and one below it on each side of the abdomen j a band or line along the 

 hinder inferior face of the thighs, extending nearly to the popliteal re- 

 gion, and a delicate one along the upper hinder face of the same, from 

 tlie groove between the superior and posterior muscles. 



* These results were sent in totheSecretary of theSmitlasonian Institution February, 

 1887. Througli the delay in publication they have been anticipated by an admirable 

 paper on the carpus and tarsus of Salientia by Mr. G. B. Howes, Proceeds. Zool. Soc. 

 Loudon, 1888, p. 141 (March). 



