; I i ■ 

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hi 



120 



IJULl.ETIN 



l^NITKO STATES NATIONAL MUSEUM. 



sonielv coloiTcl. All arc (li><tingui.shea for tiieir poworof projoctingtlio 

 toiKMio. Some of H.e spocios of Spclerpes, ul.erc tl.is organ is free all 

 ronml, can i-r.^jcct it ontirely from the i.iontli, xvhilc the acotntonfuscm 

 has almost the power of the chameleon in this respect, projecting the 

 tongue for a .listance equal to one-half the entire length of the am- 



mil * 



Appropriately to this habit, the basibranchial bone and its pair of 

 short h.vi)olivarprocesses are free from the ceratohyals, thus admitting 

 of free' movement, and the epibraiiehials are very long. In all of the 

 genera the extremity o*" the eeratoliyal is attached to the quadrate, as 

 bi the Aml»lystomi(l'ie. sliowing that it is not tliis element which is pro- 

 ji'cted. Ibit in Geotnfon and Speler|)es sp. the epibranehial is greatly 

 elongate, extending to the side of the nape and interscapular region, a 

 structure necessaiy to projectility. 



Jn tlie characters of the sca])ular and i)elvic arches this family does 

 not (IKfcr from the Amblystoniid;e and Salamandrida'. The foramen 

 which sei)arates the i)rocoracoid from the coracoiil is well marked and 

 interinarginal; in the Amblystomidie it is smaller, and .n the Sala- 

 maiulrida- marginal. The femur always i)resents a strong trochanter. 

 It is weak in Strrcochiln m<irfiinaiiiiii. In Trituriisand Diemyctylus it is 

 (piite weak, but in Salumandra stiong. 



In most of the genera of tills family the enamel does not cover the 

 entire crown of the tooth. In Siwlcrprs ruhcr, lo)){i>cau(his, and hcJHij and 

 Pkthodon (fliidnosiis and cincrciis the external part of the crown termi- 

 nates in a transverse cutting edge, while the inner extremity is more 

 prolonged, leaving a transverse depression between the two. In Sp. 

 hcllii the inner apex is transverse and prolonged a little beyond the ex- 

 ternal, while in the other Spelei])es and the I'lcfhodon ghdinnNiis the 

 inner crown is more prolonged and is incurved conic. In 1*. chwrciis 

 it is a little more obtuse. In Desmognathiis and the Amblystoinida". 

 the twoai)i('esare of equal height and are both transverse cutting edges, 

 the outer narrowed in the former. In the larva- of IMethodontida' that 

 I have examined the crowns are sim])le. The teeth of Autodax are 

 more like those of Ccecilia, or of Ilylonoinusof the Coal Measures, and 

 distiiiguisli the genus from other IMethodontida'. t They are large, 

 com]>i'ess('d, and simple. 



Tliis fiimily is more remote in its skeletal (iharacters from the Sala- 

 mandrida' and I'leurodelida' than is the Amblystomida'. Thus the 

 absence of parasphenoid brushes, the ossification of the tarsus and 

 cari)us, and (he persistence of the pterygoid bones aie characters eom- 

 nion to Die two latter and wanting in the present fiimily. On the other 

 hand, the nonprolongiition jiosteriorly of the vomers, the articulation 

 of the ccratohyal with the (piadrate, and the ampliic<e]ous vertebra', 

 belong to this family and the Amblystomida" only. The position of the 





' liWiU 



iKcr ill Sitziini'slicr. Akml, Wiss.. Miinicli, I.SrC 



tSec I'roceed. Aca.l. Nat. Sci., I'liila., 18.V,I, '-Jl. 



l>. iOlt. 



