I. On the genus Culeolus

Abstract

The genus Culeolus has been formed for a series of six new species of pedunculated Simple Ascidians, belonging to the family Cynthiidæ, and having several anatomical peculiarities distinguishing them from all hitherto described genera. The nearest ally of Culeolus is Boltenia, and these two genera have been placed together as a sub-family, theBolteninæ, characterised as Cynthiidæ which have the body pedunculated, the tentacles compound, and the branchial sac with more than four folds on each side. Culeolus is distinguished from Boltenia by its remarkable branchial sac (which will be described shortly), and by the external character that its branchial aperture is triangular, and its atrial aperture bilabiate, while in Boltenia both apertures are four-lobed.