ON CRUSTACEA BROUGHT BY DR WILLEY FROM THE SOUTH SEAS. 677 



the capitulum, and the scales of the capituhim are not very prominent. Also it is 

 a hairy species like Scalpellum hirsutum, Hoek, with which it agrees in having the 

 upper latus triangular, instead of quadrangular as it is in Scaljjellum rubrinn. But 

 the apex is not considerably produced as in Scalpellum Mrsutum. Each of Dr Hoek's 

 species was represented by a single specimen, and as there is only a single specimen at 

 my disposal, I abstain from establishing a third of these small species, without further 

 opportunity for comparison and examination. 



KOLEOLEPAS, n. g. 



Capitulum without valves. Adhesive disk forming with the basis of attachment a 

 sheath for the elastic peduncle. Labrum large, with denticulate deep emargination. 

 Palpi strong. Mandibles with cutting edge quadripartite. First pair of cirri longer 

 than the rest, the rami in all six pairs shorter than the peduncle. 



The same is from KoXeo?, a sheath, and Lepas, a kindred genus. 



By the absence of valves this genus is associated with Anelasmu, Darwin, Alcippe, 

 Hancock, and Gymnolepas, Aurivillius, 1894, the last of which, having a preoccupied 

 title, has been re-named Erenwlepas by Weltner in 1897. Species of Alepas, Sauder 

 Rang, may also be entirely destitute of valves. From all of these genera the present 

 genus is decisively separated by the combination of characters above given. The 

 typical species was found in syinbiosis with a Pagurid, and the fact that the mollusc- 

 shell inhabited by the two in common had in some way been broken into or out of 

 in the immediate neighbourhood of the cirripede's position may imply that this genus 

 belongs to the boring groups. To these Aurivillius has lately added the family Litho- 

 glyptidae, with one genus and three species, which he places in the order Abdominalia, 

 originally founded by Darwin for the single genus and single species Cryptophialus 

 minutus, but subsequently augmented by inclusion of Kochlorine hamata, Noll, 1872. 

 H. J. Hansen in 1899 (Die Cladoceren und Cirrij^edien der Plankton-Expedition, p. 52) 

 considers that the group Abdominalia is untenable, as having been based by Darwin 

 on an entire misconception of the homologies of the cirri in the t}q3e species. 



KOLEOLEPAS WILLEYI, n. sp. 



Plates LXXllI and LXXIV D. 



Dr Willoy's notes on the single specimen obtained supply several important details. 

 He describes it as a 'Sheathed and crested Cirripede living in a Turbo shell in which 

 was a Pagurid and on surface of which were many Actinians (seven large ones). 

 There was a hole in the shell exposing the end of the abdomen of the Pagurid, and 

 inside this hole was the cirripede attached, as shown above, to inside of shell.' The 

 illustration referred to (PI. LXXIV d) gives an outline of the animal with the sheath 

 reposing in the shallow cavity of a piece of shell, just as it came into my hands, 

 but the capitulum and the part of the peduncle outside of the sheath together reach a 

 length twice that of the sheath, without the twisting which has befallen the specimen 

 in spirit. Of the living form Dr Willey observes that ' It can retract itself rapidly 



89—2 



