,„^ Vol. VII, FP. 55-59 



July 30, 1920 



PROCEEDINGS 



OF THE 



NEW ENGLAND ZOOLOGICAL CLUB 



NOTES ON TWO PACIFIC COAST AMBYSTOMIDAE 



BY EMMETT REID DUNN 



In the course of work on the Pleihodontidae certain facts re- 

 garding the Amhystomidae have come to light, and they are here 



offered. . /-r. /-« i 



I am able to support Van Denburgh's contention (Proc. Cal. 

 Acad. Sci., (4), VI, p. 221) that Ambystoma ienebrosum Bd. and 

 Gir and Triicm ensaius Eschscholtz (Zool. Atlas, V, p. 6, pi. 22, 

 1833) are the same species. A skull of ienebrosum, compared 

 with the figure in the Zoologisches Atlas, shows a remarkable 

 similarity even in trivial details. The hyoids also are exactly 

 aUke. Chondrotus Cope (Amer. Nat., 1887, p. 88) is a synonym 

 of Dicamptodon Strauch (Mem. Acad. Sci., St. Petersbourg, (7), 

 XV 4, 1870), as A. tenehromm was the type species of Chon- 

 drotus. . . • i ++1 



It would reqmre a great deal more investigation to settle 

 finally the status of the generic relationship of Amhysioma, 

 Dicamptodon, and Linguelapsus. The hyoids of A. ensatum, 

 however, differ markedly from those of A. maculatum, A. opa- 

 cum and A. i2ffnnwm,aU of which are quite ahke. The larvae of 

 our eastern species have a fin-fold on the back as far as the 

 head. This is absent in ensatum larvae. 



