272 GASTEROPODES. 



ing so profusely, as pertains to the tribe. Besides, an universal collapse 

 of the parts is often incident to transference to an artificial abode : the 

 finest specimen sinks into absolute quiescence, from which it cannot be 

 aroused to display its structure. Sometimes the animal, remaining a 

 shapeless mass, as recovered from the deep, declines and dies, without 

 any symptoms of evolution, leaving all conjectures regarding its real 

 aspect, its symmetry or deformity, unsolved. 



From so great a series of difficulties, there is no animal, perhaps, 

 which has been so imperfectly represented as after nature. The most 

 distinguished naturalists, Cuvier, Delle Chiaje, De Blainville, and others, 

 have been actually unable to illustrate their own commentaries, from the 

 inability of their artists to shew the truth. 



Assuredly these facts are sufficient to stamp some value on the true 

 representation of such animals in the vigour of life. 



This is not to be obtained, however, at all seasons ; for the natu- 

 ralist is alike dependent on the quality of the specimen and on a favour- 

 able opportunity, for which he may be compelled to wait beyond the 

 endurance of his patience ; or it may be actually unattainable. 



Full grown specimens of Homberg's Doris extend eight inches in 

 length, by two in breadth and one in thickness. It is a compact, solid, 

 fleshy animal ; head a thin flap, two inches broad, with a dentate mar- 

 gin ; cornicula of singular formation, eight lines high, consisting below of 

 a socket, with a deeply indented margin, from the centre of which rises 

 a smooth pillar, crowned by several foliaceous organs, environing a pro- 

 longed central lip. A tuberculated cloak covers the whole upper sur- 

 face, with a border on each side of the back, of palmate branchiae, seven 

 or eight lines high, and spreading as much. 



The under surface shews the mouth, situate between two corru- 

 gated fleshy portions, forming the face ; the belly or sole tending to 

 a long triangular shape, with a rounded shoulder ; the whole quite 

 smooth. 



A transverse section of this animal would be irregularly quadrangu- 

 lar, slightly convex above, find flattened below. 

 No eyes have been discovered. 



