of the Genus Lej)as, 34?1 



composed of two envelopes : this, on a cursory view, does not 

 appear to be the case. To detect the inner coat, a minute 

 examination is necessary ; but if macerated a few days, the 

 two become very apparent. There is a space between the 

 two coats which gradually decreases in volume towards the 

 caudal extremity, where it is entirely lost. This space was 

 occupied by a fluid of a different nature from that found 

 within the inner envelope ; it consisted of a jelly, or mucus- 

 like substance, a rete mucosum [a mucous membrane of a net- 

 like structure], in which was contained the colouring matter 

 of the animal. The outer envelope, or epidermis, was finely 

 attenuated, and most beautifully transparent; externally, it 

 was plentifully bedewed with a watery moisture ; the inner, or 

 cutis, was much thicker, less transparent, and appeared of 

 quite another texture ; by the assistance of a common magni- 

 fying glass 1 discovered it to be fibrous, the fibres running in 

 all directions, but the strongest in parallels towards the ex- 

 tremities; hence I believe this coat to be muscular. This 

 fcict seems also to be borne out, from the animal having the 

 power of extending, shrinking, and writhing itself at pleasure. 

 Nearer the shell these fibres are obvious to the naked eye, 

 the coats become rugose or corrugated, the rete mucosum of 

 a much darker hue, and the contractile power of the animal 

 is greater here than in any other part. 



Fig, 76. b shows the shell opened, with the tentacula ex- 

 posed. The animal moves these appendages with great 

 fecility and quickness; and they serve, no doubt, the purpose 

 of seizing its food ; but I think it very likely that they are 

 also its principal respiratory organs. Each tentaculum consists 

 of many joints, which are supplied with papil lee [pimples], or 

 elevated pores, arranged transversely ; every joint has three 

 papillae, two lateral and one in the centre ; from each springs 

 a hairlike appendage, which the animal has the power of 

 rotating in all directions, in a manner nearly imperceptible to 

 the bystander. 



The inner coat likewise of some of these creatures, as seen 

 in J^g. 76. b, contained numerous very small round bodies, 

 attached to one another by cellular tissue of the finest texture 

 imaginable, and the whole was defended by an envelope of a 

 similar delicate structure, extending to nearly one third of the 

 animal's length. Each of these minute bodies, or ova (for 

 they are probably the rudiments of future offspring), was 

 surrounded by a bag containing rete mucosum, of a bluish 

 purple, in a quantity sufficient apparently to suspend the 

 ovum. 



The habits and economy of the Lepas family appear to 



z 3 



