DRODET^A. 307 



matozoa which have been introduced in the previous July and stored 

 until the yoiuig of the pre\aous year are born ; S. atra Laur. alpine 

 salamander, black, viviparous, produces only two yovmg at a birth,* 

 which are born fully developed, the uterine young have external 

 gills which absorb nutriment and oxygen, they novu-ish themselves 

 on other embryos which break down, they are able to live in water 

 if removed before development is completed f ; S. caucasica Waja, 

 Chioglossa Bocage, Spain, Portugal. Triton Laur. (Molgc Merrem), 

 aquatic salamanders, newts, with laterally compressed tail, Eur., 

 Asia, N. Amer. , pair in water, in the pairing the males of some species 

 develop a crest, oviparous, eggs glued singly to stones or water plants, 

 may attain sexual matvu-ity if prevented from metamorphosing 

 (v. Siebold, Z. /. w. Z. 28, 1877) ; T. cristatus Laur., the crested newt, 

 Gt. Britain, Eur., said to be in rare cases viviparoxis (Balfour, Comp. 

 Embryology, vol. 2), T. vulgaris L. (taeniatus), Gt. Britain, Eur. 

 Salamandrina Fitz. with 4 toes, Italy ; Tylototriton Anders., Yuiman, 

 Himalayas ; Pachytriton Blgr. China. 

 Fam. 3. Proteidae. Three pairs of external gills and two gill-open- 

 ings (hyobranchial and last branchial closed) persist throvighout life ; 

 maxillaries absent ; premaxillaries, vomer, and mandible toothed, amphi- 

 coelous vertebrae, no eyelids, fore ajid hind limbs present. Necturus 



Fig. 174. — Necturus macidatus (Rdgne animal) from Claus. 



Raf. {Menohranchus) 4 fingers, 4 toes, eyes exposed, N. Amer. ; N. 

 maculatus (M. lateralis) (Fig. 174), 1 foot, spawn Apr. and May ; Proteus 

 Laur., the olni, 3 fingers, 2 toes, eyes hidden, Camiola subterranean 

 waters, white turning black if exposed to light, spawn Apr. , eggs fastened 

 singly to stones ; Typhlomolge, waters of an artesian well in Texas. 



Fam. 4. Sirenidae. External gills (3 pairs) and gill openings (3 

 pairs, hyobranchial being closed) through life, maxillaries absent, pre- 

 maxillaries and mandibles toothless but with horny l:ieaks, amphicoelous 

 vertebrae, no eyelids, hind limbs absent, fore limbs 3 or 4 toes, S.E. Un. 

 States, young larvae unknown, in the youngest kno\\'n the giUs are small 

 and covered by the skin and the respiration is said to be aerial (Cope, 

 Amer. Nat. 19, 1885, p. 1226), later the gills increase in size. Siren L. 

 3 gill clefts on each side, 4 fingers, S. lacertina Gray, mud-eel, Pseudo- 

 branchus Gray, 1 gill cleft on each side, 3 fingers. 



Order 3. Anura.J Batrachia. 



Scaleless Amphibia without tail, external gills or gill-slits in the 

 adult state ; with four limbs. 



* Schwalbe, Zeitsch. Biol., (2), 16, 1897, p. 340. 



t V. Chauvin Z. /. iv. Z, 27, 1876. 



% Roesel v. Rosenhof " Historia naturalis ranarum noatratium," Niirn- 



