155 



While all the other species have only an opercular valve, we find in C. Lowei 

 Busk a wholly chitinized simple operculum, enclosed by a complete calcareous 

 frame, the cryptocyst being raised proximally to the operculum to the level of 

 the latter and forming its proximal boundary. This species might thus justly be 

 referred to the family Microporidce. — 



Lunularia Busk^ 

 Lunulites Lamouroux, p. p. 



The zooecia quadrangularly rounded, without frontal gymnocyst, but with a 

 depressed cryptocyst perforated by a larger or smaller aperture. No spines. Each 

 distal and each lateral wall with a number of scattered, uniporous rosette-plates. 

 The lateral walls are common to the contiguous neighbouring zooecia. The sym- 

 metrical vibracula with a long flagellum and a deeply depressed, strongly develo- 

 ped cryptocyst occur in shorter or longer rows or scattered among the zooecia. 

 No ocEcia. The species hitherto described appear in free, discoid colonies with a 

 thick basal wall covered by a membrane, the radiating furrows of which corre- 

 spond with the more or less radiately arranged zooecia. — 



This genus, which is plentifully represented in the chalk-period, has only a 

 few recent species. Of these I have had the opportunity of examining a fragment 

 of L. capulus, kindly placed at my disposal by the British Museum. 



ft will perhaps be justifiable to combine the two genera defined above into 

 one family Liinulariidae. 



Selenaria Busk, char, emend. 

 The zooezia rhombic or rhombicly hexagonal, without a frontal gymnocyst, 

 but with a depressed cryptocyst perforated by a larger or smaller aperture. No 

 spines. Scattered among the zooecia are a number of independent vibracula with an 

 arched frontal surface perforated by numerous pores or by slits. A high ribbon- 

 shaped lamina, issuing from the one lateral margin in the distal part of the vi- 

 bracularian chamber stretches over towards the opposite margin and not far from 

 this bends inwards towards the basal surface. It serves no doubt for the attachment 

 of the flabellum. Distal wall with 2 multiporous rosette-plates, and the distal half 

 of each lateral wall with a single one. Lateral walls are common to the contiguous 

 neighbouring zooecia. The ooicia, which seem to be endozooecial, appear on the 

 surface of the colony as low, rounded, pent-roof-shaped swellings. The colonies 

 are free, discoid, with a deepened basal surface perforated by numerous pores 



' 8, p. 208. 



