MUSEUM OF COMPARATIVE ZOOLOGY. 81 



conchologically it belongs with Genota as defined by Dr. Paul Fischer in hi3 

 invaluable Manual. 



The shell is closely allied to Pleurotoma cataphracta Brocchi, of the Miocene 

 of the Paris and Vienna Basins. Though the sculpture differs in detail, and 

 the fossil is more turrited, beside being sharply strongly internally Urate, the 

 G. viabrunnea may be regarded as the descendant of the fossil in a more or less 

 direct line. The several varieties even, so beautifully figured by Hoernes in 

 his monograph of the Vienna Tertiary mollusks, are reproduced in the recent 

 form. Among the five specimens I have seen there is a variation as to the 

 sculpture which would divide them into two groups, just as Brocchi originally 

 divided his Murex cataphracta. One has the spiral sculpture elegantly alter- 

 nated, a stout thread and a slender one, all over the body, and all the threads 

 minutely and prettily granulated. The other has the spiral sculpture ill- 

 defined, sparser, rude, and obsolete, that on the base showing no granulations 

 whatever. 



Soft parts. The foot is double-edged in front, rounded at the corners and 

 behind. It is nearly smooth, and like all the rest of the integument is yellow- 

 ish white (in alcohol). The tentacles are rather long, cylindrical, stout, and 

 not very pointed. The eyes are small, black, situated one third of the way 

 from the base toward the tips of the tentacles. The verge is very large, re- 

 curved, flattened cylindrical, bluntly pointed; gills two, the lamellae rather 

 short, the organs themselves rather long and of a dark greenish color. The 

 operculum normally is as in Leucosyrinx, thin, horny, elongated, pointed at 

 the anterior end, which is the nucleus. The scar of attachment is large and 

 curiously concentrically engraved, recalling the opercular scar in Purpura, 

 though not rotary-concentric as that is. 



In the Fish Commission specimens the operculum in each of three specimens 

 was abnormal, being more or less truly concentric and smaller than it should 

 have been. I suppose these specimens had lost the original operculum, and 

 the subsequent product of the gland was deformed, as is known to happen 

 occasionally in Buccinum. One of these specimens has a thickening on the 

 pillar, like a clumsy reminiscence of a plait. I noticed that the upper coils 

 of the soft parts appeared grooved when extracted, and, cutting into the spire 

 of the specimen, found that the outer lip must have been internally lirate 

 when the specimen was young, with some half-dozen obscure lira. One of the 

 specimens has obsolete lirae in the throat. They cannot be seen, but by rub- 

 bing the interior transversely with the point of a pin the invisible elevations 

 can be felt as the pin point crosses them. It is possible that the species may 

 be regularly lirate when perfectly adult, as in G. cataphracta Brocchi. The 

 specimens indicate rather that the character referred to has become obsolete 

 in the species, and only occasionally exists in special individuals. 



The dentition I am unfortunately unable to describe. The soft parts within 

 the mouth strongly recalled those of Bela as figured by Sars (Moll. Reg. Arct. 

 Norv.) ; but the gland, which in that genus is supposed to secrete venom and 



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