CRYPTOPHIALUS MINUTUS. 58 1 



the front part of the carapace or shell, which in this condition 

 was not so much truncated as in the drawing given (fig. 18) 

 of a specimen lying on its back, with its antennae protruded. 

 Some specimens formerly examined for me by Dr. Hooker, 

 had their antennae and whole ventral surface forced out- 

 wards, apparently from the endosmose of the spirits of wine. 

 The whole dorsal surface, and the over-lapping sides of the 

 carapace are elegantly punctured, and are formed of a rather 

 brittle substance, here and there supporting, especially at the 

 front end, some fine and rather long bristles, — which latter I 

 have not seen on the pupae of other cirripedes. The ventral 

 surface is very narrow towards the posterior end of the 

 animal ; it is formed of thin, structureless membrane. On 

 this surface, close to the posterior end, there is a minute orifice, 

 through which three pairs of bristles are protruded, attached 

 to (as I believe) the rudimentary abdomen ; the bristles ap- 

 parently cannot be withdrawn. 



The antennae, (fig. 18) as stated, are of large size com- 

 pared to the whole animal : they resemble, in all essential 

 respects, the same organ in other cirripedes. The ultimate 

 segment is unusually thick ;* it is terminated by five bristles, 

 one of which is longer than the others, and stands rather 

 separated from them. The disc-segment is large, nearly 

 circular, with the broad edges transparent and membranous; 

 on its posterior edge there is a single small spine. The 

 second or main segment, counting from the base, has a 

 single spine on its upper margin, close beneath the spine 

 on the disc ; it is articulated to the disc-segment, a little 

 way from the disc itself, — which is a peculiarity I have not 

 elsewhere noticed. The basal segment is thick and not so 

 short as usual. These organs are furnished with powerful 

 muscles. They are generally protruded alternately; and 

 by the adhesion of the sucker-like disc, the animal drags 

 itself along. The sucker-disc has great play, and when 

 observing specimens alive, I compared its action to that of 



* As I have given, in my former volume on the Lepadidae, p. 2S6, so many 

 measurements of the antennse, I may here add those of Crystophialus, — the 

 length from the end of the disc to the end of the second segment, (formerly 

 called by me, erroneously, the basal,) is 5 =g D ths of an inch ; the greatest width 

 of the second segment, S5 9 oth s ; the length of the little ultimate segment, 

 girths, and its width under booths of an inch. 



