ACADEMY OF NATURAL SCIENCES. 



57 



strephes giganteus D'Orb in large numbers, and " hundreds " of a species of 

 Argonauta washed ashore last spring as far north as Santa Cruz Island, as I 

 was informed by Dr. Shaw, who presented specimens to the State collection. 



Fig. 14. 



Aplysia Linn. 

 A. californica Cooper. State Collection, species 1045. 



Form and external appearance as usual in the genus. Length fifteen inches, 

 breadth five, height about the same. Color pale gray or greenish, becoming 

 purplish on the side, folds of mantle with scattered white specks, from which 

 an irregular network of brown lines extends over the rest of the body, inter- 

 spersed with large brown blotches. Inner surface of mantle varied with alter- 

 nating painted bars of white and dark brown interlocking together. Sole of 

 foot black. Eyes very minute and black. 



Shell contained in the substance of the mantle cartilaginous, translucent, 

 trapezoidal or hatchet-shaped, margins rounded, slightly convex above, the 

 nucleus or centre in old specimens distant from the posterior end or apex. 

 Faint radiating lines diverging from the nucleus, crossed by an irregular net- 

 work of darker lines, all ending abruptly at some distance from the margin, 

 which has thus a wide, nearly transparent border. An accessory plate arises 

 on the inner surface from the nucleus, spatulate in form and slightly raised. 



The two younger specimens have the clear border and accessory plate less 

 developed, and very young ones do not probably show these characters at all, 

 but resemble the typical Aplysia in the form of the shell. On this account I 

 am unwilling to constitute it a new genus, but propose to call it a sub-genus 

 under the name of Neaplysia. 



There was no appearance of a multiplication of shells, said to occur in old 

 specimens of Aplysia. Not having any full description of the internal anatomy 



