126 DOLABRIFERA. 



D. sowERBYi Guilding. PI. 34, figs. 9, 10. 



Soft parts unknown. Shell tortuous, subtrigonal, beak tortuous, 

 thrown backwards, produced, apex small ; basal margin rather 

 straight, upper margin concave, external margin sinuated below the 

 middle, roundly acuminated at the end ; disk centrally depressed at 

 the back. (Sowb.) 



St. Vincent, West Indies. 



Dolabrifera sowerbyi ( u Guilding Zool. Journ." according to Sow- 

 erby, but not in the Zoological Journal), Sows., Conch. Icon., xvi, 

 pi. 1, f. 2. 



The tortuous depression in the dorsal disk, and the acuminate 

 termination of the outer margin distinguish this species. (Sowb.) 



D. (?) ORNATA Swainson. Unfigured. 



Swainson has given an imperfect description from an unpublished 

 colored drawing by Guilding, of a species perhaps belonging to this 

 genus. The locality is unknown, but probably St. Vincent, West 

 Indies. As none of the important structural characters are known, 

 the generic name will not stand, if the creature proves to belong to 

 some known genus ; but the species, on account of its brilliant col- 

 oring, will probably be recognized sooner or later. It is not known 

 whether the drawing was enlarged or natural size, so the dimensions 

 given may prove incorrect. Swainsoii's description here follows : 



Thallepus ornatus. Body more slender and fusiform [than 

 Aplysia] ; the lobes of the mantle [pleuropodial lobes] short and 

 incapable of being used for swimming; tentacula two, large, ear- 

 shaped ; eyes not visible ; lower pair of tentacula wanting. A most 

 beautiful figure of a species to which I give this name, is among 

 Guilding's drawings, but without any description ; it was evidently 

 finished from the living animal. The general color is sea-green, 

 covered with minute black and white dots. The edges or crests of 

 the reflected mantle [pleuropodia] have a broad edging of the 

 richest orange, bordered on their outer edge with a line of deep 

 black ; the tentacula are also orange, and formed like those of 

 Aplysia. Total length about 3? inches. The only memorandum 

 on the drawing is " eyes not visible." Whether this had any cover- 

 ing over the branchia I have no means of judging (Swains., Treatise 

 on Malacology, or Shells and Shell-fish, pp. 250, 359. 1840). 



This form may prove to be the same as one of the West Indian 

 species known from the shell only. 



