352 PROCEEDINGS OP THE NATIONAL MUSEUM. vol.53. 



"Named in honor of Dr. Thomas Antisell, one of the early geol- 

 ogists of California." 



I have not seen a specimen of this species and quote the published 



text and figure. 



Genus STILIFER Broderip. 



Stilifer Broderip, Proc. Zool. Soc. London, 1832, p. 60. Type Stilifer astericola 

 Broderip. 



Melanellids with a mucronate apex, globular form, and the inner 

 lip not appressed or adnate to the attenuated base of the preceding 

 whorl. 



STILIFER ASTERICOLA Broderip. 



Plate 49, fig. 2. 

 Stilifer astericolus Broderip, Proc. Zool. Soc. London, 1832, p. 60. 



Shell large, globose, with a slender acuminate mucro, which is 

 usually decollated; tliin, semitransparent, bluish-white. Postnuclear 

 whorls strongly inflated, marked by strong incremental lines which 

 are almost threadlike and irregularly disposed. The appressed por- 

 tion of the whorls appears as a bluish band. Body whorl slightly 

 flattened in the middle. Periphery well rounded. Base short, 

 strongly rounded, marked Hke the spire. Aperture large; posterior 

 angle acute; outer lip very thin, strongly curved, and strongly pro- 

 tracted in the middle to form a clawlike element; inner lip slender, 

 strongly curved; parietal wall covered by a scarcely perceptible 

 callus. Radula absent. 



I have seen 16 specimens collected in the water-vascular system of 

 starfish by the CaUfomia Academy of Science Galapagos Expedition 

 at Tagus Cove, Albennarle, Galapagos. Two of these are Cat. No. 

 322286 U.S.N.M. One of these, the specimen figured, has 5^ whorls 

 and measures — length, 8.6 mm.; diameter, 6.3 mm. 



Broderip 's specimens were collected by Hugh Cuming at Hood 

 Island, Galapagos, and I find the following interesting remarks 

 on them in the publication cited: 



"The arrival in this country of the shell above recorded, with the 

 soft parts, has afforded data for a generic character indicating a dis- 

 tinct family among the PectinihrancTiiata, the form and disposition 

 of whose mantle differs from that of any other genus in the order. 

 This mantle (which in Stil. Astericola is of a green hue) is thick, fleshy, 

 and cup-shaped, with a small aperture at its base and a free posterior 

 margin enveloping the soft parts and the last whorls of the shell, 

 which has thus somewhat the appearance of a small acorn set in its 

 cup. On the ventral aspect of this mantle is the rudiment of a foot ; 

 and from the small basal aperture a retractile 'proboscis (which when 

 exserted is as long as the whole animal) is protruded. At the base of 

 this proboscis are two thick, round, somewhat pointed tentacula; and at 

 the base of them are the eyes or rather ocular specks without pedi- 

 cles. The brancMa is placed on a single stem. At the base of the 



