1898.] NATURAL SCIENCES OF PHILADELPHIA. 249 



Jaw (PI. XVI, fig. 98) strong, opaque, with 8-14 wide flattened 

 ribs. 



Radula with 44-1-44 teeth. Centrals tricuspid, laterals bicus- 

 pid, the ectocones small. Marginals formed by shortening of the 

 basal-plates, having the mesocone short, ectocone simple or on some 

 teeth bifid (PI. XVI, fig. 90). 



Epiphallus stout, cylindric, curved, with the usual constriction, 

 peduncle and muscle at base. Vas deferens extremely long, elabor- 

 ately twisted and tangled. Vagina long, the spermatheca duct 

 about as long as the spermatheca. Albumen gland very large, long 

 and tongue-shaped. Ovo-testis a very compact mass showing exter- 

 nally only the rounded-polygonal ends of the closely packed folli- 

 cles. In two typical individuals from Seattle (Mus. no. 71,072) the 

 measurements are : a (fig. 55), length of swollen epiphallus 12.5 

 mm., of extended vas deferens from summit of epiphallus to base of 

 same 92 mm. ; of albumen gland 28 mm. ; length of animal 80 mm. 

 b (fig. 57), length of epiphallus 14 mm.; of vas deferens 114 mm. 

 The ratio of length of epiphallus to that of vas deferens as measured 

 above is about 1 : 71 or 8. The original of fig. 58 is a small speci- 

 men, perhaps not fully adult. 



Type locality, Discovery Harbor, Puget Sound (Pickering). Also 

 occurs at Olympia (Hemphill), Seattle (Hemphill, Randolph), and 

 doubtless throughout the Puget Sound region generally. 



P. foliolatum is very closely allied to P. Andersoni Coop. It is 

 larger, more elongated, with the solid portion of the tail, or that sub- 

 ject to amputation, longer in proportion than in Andersoni. In 

 living specimens a mucous pore is visible at the tail, but this is not 

 noticeable externally in alcoholic examples. The light dorsal line 

 is occasionally indistinguishable. 



The jaw forms probably intergrade with P. Andersoni; but the 

 teeth differ quite perceptibly in the shorter, blunter cusps of the 

 outer laterals and inner marginals. This is one of the best specific 

 characters. 



The form described by Binney as Phenacarion Hemp hi Hi does 

 not seem to offer sufficiently tangible points of difference from folio- 

 latum to stand as a species, even were the name not preoccupied. 

 It is said to be " more slender and more pointed at the tail than 

 foliolatus. The body is a bright yellow with bluish-black reticula- 

 tions. The edge of the foot and the foot itself are almost black. 

 Shield irregularly mottled with fuscous. The body also is irregu- 



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