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the form of tlio cnrlilagos of tlio larjiix. Tlie size iiiid niiiiilHT of (lie 

 pulmonary cells vuiy coiisidoraltly. Amoiif; Ilylida', o.siK-cially tiioso 

 speck's with a loiiil voicf, tlicy are fewer and larger than in Discogloa.si- 

 die and Scaphiopida'. The forms of the sinus, auricles, venlricile, and 

 bulbus arteriosus, the throe aorta bows, of which the median foruj the 

 aorta roots, etc., appear (piite identical externally in the Discoglossus, 

 Scapliioi)us, and rhyllomediisa. Internally the two former present the 

 known characters of the Annra, /. e., the union of the distinct ducts of 

 the first (i)nlmonary) and second (aortic) aorta bows thro'ighont much 

 of their length, the separate union of the two former and (tontinuance 

 on the left side of a high free septum of tlu» bulbus, till they are finally 

 turned over the riglit division toward the right, and have a common 

 issue from the ventricle. A conic pocket valve is at the origin of the 

 bifurcation of the ductus communis of tlie second and third aorta bows, 

 but none in any part of the course of the pulmonary. 



The general characters of the venous system have iteen (b'scribed on 

 page 10. The researches of Ifochstetter * and HowesI Inive shown that 

 the cardinal veins do not disapi)ear in all of the Salientia. Ilochstet- 

 ter in fact believes "that the vena cava inferior, instead of being 

 throughout its whole extent a i>rimarily independent vessel, is a com- 

 pound structure, the product of a fusion between a late-formed hepatic 

 vessel and one or both of the posterior cardinal veins" (Howes). In 

 IJatrachia the postrenal portions only of the (iardinals go to form the 

 vena cava i)osterior, and the prerenal p(»rtions disappear or remain I's 

 azygos or hemiazygos veins. Their persistence is shown to hi' fre 

 quent in theDiscoglossida', in l>ombinator (llochstetter Howes), Alytes 

 (Howes), and Discog'ossus (Howes). It is wanting in other Salientia, 

 incbuUng the Aglossa, L'ehtdytida', and IVlobatidai (Howes). 



The general character of the brain in the Salientia may be gathered 

 from Plate o(!. As I omitted, by an oversight, to refer to the charac- 

 ters of this region in my anatomical introduction (pp. 1-12), I introduce 

 here some rennirksoii its peculiarities in the I'roteida, IJrodela, etcr., as 

 well. In the Proteida (Necturus, (Ig. 1) the tlialamencephalon is ex- 

 posed by the nonprodiuition posteriorly of the prosencephalon. In 

 Urodela generally (Plate U)) and in Salientia it is moderately exposed : 

 in Ca'ciliida- (Plate 5(», tig. ;j) it is generally concealed. In all the tailed 

 forms there is a large vascular "supraplexus" protiuding from between 

 the hemispheres. Posterior to this the ei)iphysis appears; it is small 

 in all the orders. The hypoi»hysis is on the other hand large. The cere- 

 bellum (epencephalon) is a mere commissure in the entire class. The 

 diaccelia, niesoco'lia, and metaccelia are only .sei)arated by slight con- 

 .strictions of their walls. The metac(elia is covered in the Salientia by 

 a triangular choroid plexus (Plate '>{> p. c). In Protei<la, Urodela, and 

 Trachystomata the olfactory lobes (rliiniMicephala) are distinct; but 



*Mori)li:)liiv;isoIiCH Jahrbiicli, IH^r, p, 1l'.>; AiiiitDiiiiselicr Aiizoiger, IHd*, 517. 

 tProceel. Zoiil. .Soe. London, ISS-*, p. l>>. 



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