20 LEPADID^:. 



mouth : the fact, however, of its being prolonged to the 

 anus, which is in a different position in the larva and 

 mature state, shows that the stomach serves, at least, as 

 an excretory channel. Besides the stomach, the several 

 muscles already alluded to, and much pulpy and oily 

 matter, the only other internal organs consist of two long, 

 rather thick, gut-formed masses, into the anterior ends 

 of which the cement-ducts running from the prehensile 

 antennas could be traced. These masses are formed 

 of irregular orange balls, about '001 of an inch in 

 diameter, made up of rather large cells, so to have a 

 grape-like appearance, held together by a transparent 

 pale yellowish substance, but apparently not enclosed in 

 a membrane : these masses lie rather obliquely, and ap- 

 proach each other at their anterior ends ; they extend 

 from above the compound eyes, to the cseca of the stomach 

 to which they cohere, but in young specimens, they ex- 

 tend some way beyond the caeca, between the folds of the 

 carapace. The two cement-ducts, at the points where 

 they enter these bodies, expand and are lost ,• at this point, 

 also, the little orange-coloured masses of cells have the 

 appearance of being broken down into a finer substance. 

 Within the cement- ducts I saw a distinct chord of rather 

 opaque cellular matter. We shall presently see, that these 

 gut-formed masses are the incipient ovaria. 



The Young Cirripede within the Larva. — Several times 

 I succeeded in dissecting off the integuments of the 

 lately-attached larva, and in displaying the young Lepas 

 australis entire. The following description applies to the 

 Cirripede in this state ; but for convenience sake, I shall 

 occasionally refer to its condition when a little more 

 advanced. I may premise, and the fact in itself is curious, 

 that the bivalve-like shell of the larva, together with the 

 compound eyes, is first moulted, and some time afterwards, 

 the inner lining of the sack, together with the integu- 

 ments of the thorax and of the natatory legs : hence, I 

 often found specimens, which externally seemed to have 

 perfected their metamorphoses, but which, within their 



