70 GENUS LEPAS. 



distinguishable,) of the carina is seated just above the 

 embedded fork (or disc in L. fascicularis), at the point 

 where the inflection takes place ; hence the main growth 

 of the carina is upwards, — the fork, however, being of 

 course, likewise added to at its point : in L. fascicularis, 

 the growth is both upwards and downwards. 



Peduncle and Attachment. — The peduncle is generally 

 quite smooth : though with a high power its surface may 

 be seen to be studded with minute beads, or larger discs, 

 of yellowish and hard chitine ; in the young of L. aus- 

 tralis, and I suspect of some other species, it is covered 

 with very minute spines. The peduncle in this genus 

 attains its greatest development. The cement-tissue de- 

 bouches, I believe, only through the functionless larval 

 antennae, except in one species, L. fascicularis, in which a 

 ball of this substance is formed in a most peculiar manner 

 round the peduncle (PL I, fig. 6), apparently for the purpose 

 of serving as a float, as will be presently described. 



Size and Colour. — The species of this genus are the 

 largest of the Pedunculata, with the exception of some 

 Pollicipes : even in the smallest species (£. pectin ata), 

 the capitulum sometimes attains a length of about half 

 an inch. The peduncle varies much in length in the 

 same species: in L. anatifera, it is occasionally above a 

 foot long. The colours of L. anatifera, L. Hillii, and 

 L. anserifera, are very bright and striking ; the membrane 

 bordering the valves and that round the top of peduncle 

 in two of the species, is of the brightest scarlet-orange ; 

 the valves, owing to the under -lying corium, are pale 

 blueish-grey, and the interspaces between them dark 

 leaden-purple. The cirri and tropin are generally dark 

 purple or lead-colour. 



Filamentary Appendages. — These are attached to be- 

 neath the basal articulation of first pair of cirri ; they vary 

 in the several species, from one to five or six on each 

 side, the lowest being always the longest. Several of 

 them are occupied by testes. In L. pectinata, generally, 

 not even one is developed. They are subject to great 



