528 LEPADIDJ3. 



the female Alcippe had partially assumed characters con- 

 fined to the males of the other genera, it would assuredly 

 stand amongst the Lepadidae. Independently of this com- 

 parison with the foregoing males, the affinities of Alcippe 

 arc so special to several genera amongst the Lepadida?, that 

 it seems unnatural to force it out of the position which it 

 well occupies between Ibla and Anelasma, and place it in 

 another family by itself : thus, in being bisexual, and in the 

 general character of its very curious males, Alcippe shows 

 an affinity to Ibla and Scalpellum ; and to the former of 

 these genera it is related in several particulars, such as in 

 the body being lodged within the peduncle, and in the 

 structure of the larval antennae, &c. : to Anelasma and 

 Alepas it is allied in the general character, and to a certain 

 extent in the muscles, of the capitulum ; Anelasma, also, 

 has all its cirri to a certain degree rudimentary, and 

 Alepas cormita has the inner rami of the fifth and sixth pairs 

 of cirri, — namely, the very same rami which are so curiously 

 modified in Alcippe, — small, destitute of muscles, and func- 

 tionless for their proper purpose : to Anelasma and Litho- 

 trya it is allied in the peculiarity of the lower end of the 

 peduncle becoming elongated by growth, and in being 

 imbedded ; and to Lithotrya by its powers of excavation and 

 manner of attachment. Now, I believe it generally holds 

 good that when a form is really distinct from another group, 

 its affinities are general, or only in a slight degree special to 

 the members of that group. Nor, indeed, can it be asserted 

 that Alcippe differs much more, somewhat more it certainly 

 does, from the other genera, than does Anelasma, with its 

 more singular mouth, spineless rudimentary cirri, and fim- 

 briated peduncle; and I have never regretted having in- 

 cluded this genus amongst the Lepadidae. Hence, after 

 much consideration, I have resolved to consider Alcippe as 

 one of the Lepadidae, though so curiously modified,* and 



* Adrien de Jussieu, in his 'Memoir on the Malpighiaceoe,' 'Archives du 

 Museum/ torn. 3, p. 8G, when speaking of the characters afforded by the 

 degraded flowers, which in certain genera are borne together with ordinary 

 flowers, makes the following observations bearing on the question here discussed, 

 viz., whether or not to include Alcippe amongst the Lepadidae. " Ces examples 

 peut-etre aideront a comprcndre comment a des genres d'une organisation assez 

 compliquee, viennent quelquefois s'en rattacher d'autres d'unc organisation 

 braueoup trop simple en apparence, membres appauvris et degrades d'une 



