166 W. Lilljeborg on the Genera Peltogaster and Liriope. 



areolar tissue ; this lines the internal cavity, and consequently 

 embraces the ovaries. It is probably this membrane that Rathke 

 regards as a stomach (ventricule) ; and when he found eggs in it, 

 he was led to believe that the stomach of these animals also 

 performed the function of a matrix. 



The two parts which both Rathke and the author regard as 

 male organs [vesiculm seminales ?) form, in Peltogaster sulcatus, 

 opake sacs filled with a cellular matter and furnished with a 

 long neck (figs. 10 a & 11). This neck is fixed, beneath and to 

 one side of the primary ovaries, to the inner surface of the lining 

 membrane of the body-cavity. These parts are attached beneath 

 the organ of adhesion, as mentioned by Rathke. Their csecal ex- 

 tremities are directed forwards, as described by Rathke. As the 

 author's specimens were preserved in spirit, he could not ascer- 

 tain whether these sacs contained spermatozoids. He hints that 

 they may be cement-glands, but, as they do not appear to be 

 connected with the ovaries, from which, as asserted by Darwin, 

 the cement-glands originate, and as he could not discover any 

 connexion between them and the organ of adhesion, which ought 

 to be formed by their secretion, he does not regard this function 

 as probable. That Peltogaster possesses cement-glands is indi- 

 cated by the structure of its organ of adhesion and the mode in 

 which this organ is fixed to the skin of the abdomen of the 

 Pagurus. On comparing the dilated disk of Peltogaster Pa- 

 guri (fig. 8) with that of the basal membrane of Coronula 

 balcenaris figured by Darwin (Mon. Cirrip. ii. pi. 28. fig. 1 a), 

 there appears to be a considerable resemblance between them. 

 The margins of the organ of adhesion are more or less united to 

 the skin of the Pagurus, so that, in separating them, fragments 

 of the skin, or at least of the epidermis, remain attached to the 

 margins of the organ*. 



The ovaries at first present the appearance of two sacs placed 

 very close together; they are elongated, opake, and a little 

 thickened behind (PL IV. fig. 9). They are situated on the 

 inferior wall of the body-cavity, immediately behind the organ 

 of adhesion, upon the tegumentary membrane, which is much 

 thicker in this spot. They are separately enveloped by a cellular 

 membrane with different formative materials. Their walls are 

 thick and opake. The structure of the contents is acinose. 

 When compressed and magnified 200 diameters, the ovules, with 

 their germinal vesicle, are clearly seen enveloped in a tenacious 

 matter, which is probably a future cement, as this, according to 

 Darwin, issues in a similar form from the primitive ovaries of 



* According to Darwin, the cement of Coronula balcenaris penetrates the 

 epidermis of the Whales, and becomes confounded therewith in the way 

 above described. 



