286 



This species is present in great numbers from the Formosa Channel, Lat. 

 23" 20' N., Long. US" 30' E., 17 fath. (Andrea). 



Adeonella Jellyae n. sp. 



(Pis. XIV, figs. 4a-4g, 4h, 41). 



The zooecia, the finely tuberculated surface of which is covered by a brown- 

 ish violet membrane, are rhomboidally hexagonal or vase-shaped and provided 

 with scattered pores, which are most numerous in the marginal portion. The 

 primary aperture, which only in the very youngest zooecia lies immediately on 

 the surface of the colony, has an almost quadrangularly rounded anter, the two 

 almost parallel lateral margins of which meet in a curve. The more or less con- 

 vex poster is provided with a sharply bounded, quadrangularly rounded sinus, 

 the breadth of which is about one-third of the aperture and is almost as long 

 as it is broad. There are well-developed hinge-teeth and a well-chitinized 

 operculum. The secondary aperture, the development of which passes through 

 many stages, attains the structure peculiar to the genus only in very old zooecia. 

 It is thus at a certain point of time provided with a large rounded sinus, the 

 proximal part of which finally becomes a pore. The form of the real secondary 

 aperture varies between round and semi-elliptical, often with an almost straight 

 proximal margin. In the distal half of the zooecium there are 14—16 uniporous 

 rosette-plates. 



The gonozooecia are scattered in smaller numbers among the ordinary zoce- 

 cia. They are only a little larger than the latter and have an aperture of a some- 

 what different form. Its anter is almost semi-elliptical, and its slightly convex 

 poster is provided with a rounded sinus, which is at its starting point about 

 half as broad as the aperture. « 



The avicularia have a rather long, triangular mandible and appear both as 

 independent and as dependent. The former, which may attain a size similar to 

 that of the zooecia and which have a rhomboidally vase-like form, are scattered 

 over the surface of the colony, singly or in groups of up to 4. The dependent 

 avicularia, which are not only found on the zooecia and the gonozooecia, but in 

 rare cases also on the independent avicularia in a number of 1 — 2, are subject 

 to some variation both with regard to number and position. There are generally 

 two proximally to the aperture, which have the points turned obliquely proxi- 

 mally and towards the centre, but one of them may be directed distally in a 

 smaller number of zooecia. Very often we find proximally to these two still a 

 third, the position of which may be very variable. 



The colonies appear as bilaminate, foliaceous, folded and lobed expansions, 



