Descriptions of New, or Little Known, Polyzoa. Ill 



Family Microporellid.e. 



Microporella scandens, n. sp. Plate IV., fig. 7. 



Alysidota ciliata, M'G. 



In 1869 I described a form which I referred to Busk's 

 genus Alysidota as A. ciliata. I am, however, satisfied 

 that Alysidota is founded on insufficient characters, and 

 that this species is rightly referred to Microporella, one of 

 the commonest species of which is the well-known M. 

 ciliata, so that it is necessary to give it a new specific 

 name. I have only seen one specimen, which consists of 

 a chain of eight cells, four surmounted by ovicells, running 

 up a branch of Bicellaria grandis. The cells are pyrif orm. 

 The mouth is arched above and straight below. There are 

 four or six long, articulated oral spines. The surface is 

 smooth, and presents no marks except the suboral pore, 

 which is small, and semilunar. The ovicell is of large size, 

 rounded, and the upper edge, where attached to the cell 

 above, is slightly dentate in the same manner, but not so 

 distinctly as occurs in ill. Mahisii. 



Microporella diadema, M'G. Plate IV., figs. 3 — 6. 



This beautiful species varies considerably in the appear- 

 ance of the surface of the cell and ovicell, according to the 

 amount of calcareous deposit, in the size of the spines, the 

 form and size of the suboral pore, and the situation and 

 direction of the avicularia. In fact, it is even more variable 

 than its well-known congener, M. ciliata. 



In the typical form the surface is only slightly calcareous, 

 smooth or with a few impressions round the margin. The 

 suboral pore is not more than a third part of the width of 

 the mouth, and is rounded or semicircular. The avicularia 

 are situated on one or both sides on a level with, or rather 

 above, the pore, and are directed outwards and slightly 

 downwards. The front of the ovicell is smooth, surrounded 

 by a prominent broad band of radiating beaded ridges. 



The following varieties, which I have figured, seem 

 worthy of distinction: — 



Var. lunipwncta. — In this variety the cells are broad, 

 smooth, and slightly grooved at the edges. The suboral 

 pore is a narrow, lunate slit, equalling the mouth in width. 

 The avicularia are of large size, situated below the pore, and 



