MUSEUM OF COMPARATIVE ZOOLOGY. 209 



ceived from Dr. Cooper, is drawn by Mr. Cockerell on Plate VII. Fig. C. Mr. 

 Cockerell has shown me that I have confounded with it another species, which 

 he proposes to call P. fasciatum. See next species. 



Prophysaon fasciatum, Cockerell. 



This species is described by Mr. Cockerell as distinct from Andersoni, with 

 which I have formerly confounded it. (2d Suppl. to Vol. V., p. 42.) It has 

 a dark band on each side of the body, running from the mouth to the foot. 

 To this must be referred the descriptions of animal, dentition, jaw, and geni- 

 talia formerly published by me as of Andersoni. 



I am indebted to Mr. Theo. D. A. Cockerell for a figure and description of 

 this species. The former is given on Plate VII. Fig. A, while the latter is 

 given here in the words of Mr. Cockerell, whose name must consequently be 

 associated with it as authority : — 



Length (in alcohol), 19 mm. Mantle black, with indistinct pale subdorsal bands, — 

 an effect due to the excessive development of the three dark bands of the mantle. 

 Body with a blackish dorsal band, commencing broadly behind the mantle and 

 tapering to tail, and blackish subdorsal bands. No pale dorsal line. Reticulations 

 on body squarer, smaller, more regular, and more subdivided than in P. Andersoni, 

 Cooper. Penis sac tapering, slender. Testicle large. Jaw ribbed. 



Prophysaon cceruleum, Cockerell. 



Plate VIII. Fig. I, J. 



In the Nautilus, 1890, p. 112, it is thus described : — 



Length (in alcohol), 22.j mm. ; in motion, 43 mm. Body and mantle clear blue- 

 gray, paler at sides, sole white. Mantle finely granulated, broad, without mark- 

 ings. Length of mantle, 7 mm. ; breadth, 5 mm. Respiratory orifice, 2-£ mm. from 

 anterior border. Body subcylindrical, tapering, pointed. (In one specimen eaten 

 off at the end.) Distance from posterior end of mantle to end of body, lOf mm. 



The reticulations take the form of longitudinal equidistant lines, occasionally 

 joined by transverse lines, or coalescing. Sole not differentiated into tracts. Jaw 

 pale, strongly ribbed. Liver white. 



Mr. Binney sends me colored drawings of the living animal ; the neck is long 

 and white, or very pale. Mr. Binney has examined the jaw and lingual, and finds 

 them as usual in the genus. 



Several specimens were sent from Olympia, Washington, by Mr. Hemphill to 

 Mr. Binney. 



P. cceruleum is an exceedingly distinct species, distinguished at once by its color 

 and the character of its reticulations. 



Prophysaon cceruleum, var. dubium, n. var., Cockerell. 



Length (in alcohol), 8 mm. Length of mantle, 4 mm. Distance from posterior 

 end of mantle to end of body, 3£ mm. Mantle broad, with four bands composed 

 of coalesced black marbling, very irregular in shape, and running together anteri- 

 orly. Body dark, tapering. Sole pale, its edges gray. Liver white. 



vol. xix. — no. 4. 14 



