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" I 



i; 

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506 BULLETIN 34, TNITKI) STATES NATIONAL MUSEUM. 



FlO, 4. .Iniiiliiumu hkyjhk. 



5. TyphloiuctcH comjirinniaiudiiii, from tlii' Rflizi-. 



(!. Dirmophis mfjicuHim, witli tin- ipiadrnti^ lioiio turned up, lixpiising its iiifi- 

 rior face, ami that of tho nuatlratiiiugal: 4a, the ((iiatlrate in normal \»<. 

 sition. From Mexico. 



7. ChoiidrotiiH tcnrhroDiix larva, 2.'i(l mm. 



8. Chomlrotm Uinhromin, adult. 



9. Amhlyntoma ti<iriiium larva ; Hquamosal removed. 



10. Amhijjslitino puiictatiim, adult. 



11. Ilfmidiivtyliiim sciitatiim. 



12. liatrnchoKcps atienuntus. 

 i;t. (luriiiopliUiii porphiinUciin. 



14. Ph'tliodon (jlutinoHun; s(iuamosal removed. 



15. Autodar luf/uhfin; sipiamosal removed. 

 IG. iSpvlvrpen rithcr: sqiiiimosal removed. 



PLATE XLIX. 



Tho relations of the <iuadrate, Htapcdial, and hyoid npitaratus in Umdela and S.ili 

 I'litia. Figures twice natural size, with seiiarato details larger. FrointJope, Anier- 

 ican .Journal of Morphology. 



Vui. 1. iMnmonniilhiiD iii'ira, the siiuamosal in place; n, stajjes sepiirate and en- 

 larged. 



2. Sahimmidra viacnlatti j ; the squamosal separated. 



3. DkmyclyJiiK torusux, squaniosal removed; o, separate sciuamosa'. 



4. DiemyctyhiH riridi'nceiix, three times natural size, the squamosal removed ; '.'n. 



the s(|uamosal, external side; fc, apex of ceratohyal. with hyo(|uadiatr 



ligament. 

 .">. Sinn hicertuia |. H([uamo.sal in place. 

 (). Disvoijloxxiin pivtiix, partly posterior view ; «, ear-hones an<l origin of eer.itn- 



hyal, enlarged. 



7. liiifo UntiyinonHs amcrkHnitu, tht; squamosal removed; a, the acjuamosal >i\i- 



arate. 



8. Spea hammondii, tlio squamosal removed; n, the bqinunosal; h, the ''ai- 



bones. 



9. Hyla gratiom, tho squamosal removed; a, the squamosal; h, the ear-boms 



and cartilages in protile, the cartilages of the tympanum divided by ver- 

 tical section ; c, the ear-bones and cartilages undivided, external view. 



10. XenopuH cakardtus, partly from behiml, with squamosal in i>Iace. 



11. Sk'irocyclopa iHcfrts.srt/H'*, sfiuamosal in place; «, stapes and ear-bones .lud 



cartilages. 



12. Rana prctlosa, s((uainosal in place: I'ar-bones and vertically divided carti- 



l.ages. 



PLATE L. 



The quadrate, hyoid, and auditory elements. From Cope, American Jouruiil of Mm- 



phology, 18d^. 



Fig. I. Ranarirescciis, x 2; a, squamosal bone; fc, ear-bones without epistapedial : x 1 



2. Rana lurenccnx, larva with hind legs, and developed fore legs concealed ; tin- 



skull X2; a, the hyoid apparatus from beloiv x 4. 



3. Rana cateshiana, advanced larva, skull, without hyoid elements, except 



ceratohyal X 3. 



4. Trinierorh(ichi8 insiynis Cope; left posterior part of skull from below, the 



mandible in place; natural .size. P^rom the Permian bed of Texas. 



i 



. 



