BRYOZOA FROM ZANZIBAR. 515 



In the submandibular part of the aviculavium there is a 

 liammer-sbaped thick chitinous piece for attachments of muscle. 

 The proximal muscles are in several bundles and are attached to 

 the base of the tentacles. 



Lepralia is a genus which we have long wanted to see brought 

 into order, but certainly further work is required, Hincks made 

 a group Lepralia^ and, no doubt, on the whole the species of his 

 gi'oup are closely related, but he unquestionably placed some 

 there which should have gone in his Schizoporella and other 

 genera. Neviani, taking species with a horse-shoe aperture, 

 made a genus Hippoporhia^ but he still retained some which 

 must be separated, and ver}^ little was gained by his new 

 name. In Lepralia the operculum is usually thick and has a 

 strengthening band at each side with the muscles attached near 

 the distal end of the band. The sides of the operculum are either 

 straight or much contracted where the lateral teeth of the 

 aperture occur. This will remain a fairly large group even when 

 extraneous species have been removed, but we hardly know where 

 Levinsen would place them, as hardly any of them are mentioned. 

 L. adpressa, L. Mppopus, L. rectiliveata Hincks, find no place. 

 Lepralia feegensis is made the sole rejDresentative of a new genus 

 Hippopoclina^ but the characters given seem insufficient for 

 separation, as there are a considerable number with the same 

 general characters. 



Some Lepralia Levinsen places under Smittiiia, a new name for 

 S'mittia, but the true Smittia to which he alludes have a very 

 thin membranous operculum with straight pioximal edge hardly 

 separated from the frontal membrane, and there is usually a lyrula, 

 which is perhaps a structural correlation with the thin mem- 

 branous operculum ; further, there are very small oral glands 

 often partly attached to the tentacular sheath. I find it quite 

 impossible to place Lepralia jxdlasiana and its allies side by side 

 with Schizoporella auriculata Hass., S. linearis Hass., S. triangula 

 Hincks, etc., as the group seeims ver}^ unnatural. 



Levinsen's Cheilopora* contains species some of which have the 

 ovicelligerous zooecia with a quite differently shaped aperture fi'om 

 that of the ordinary zoceoia, as, for instance, Lepralia circumcincta 

 Neviani, a species found fossil, but also living, fi'om Naples, 

 Capri, and Oran (Algiers) ; whereas L. longipora MacG. = Z. prce- 

 lovga Hincks, and L. prcelucida H. have large raised perforated 

 ovicells. This dimorphism occurs in several Lepralidte, but in 

 Schizoporellidaj I only remember it in ;S'. subimmersa MacG. We 

 hardly know yet how far these characters are reliable for generic 

 divisions. 



Such forms as L. adpressa Busk, L. liip)popus Sm., L. recti- 

 lineata H., and the bulk of Avhat we have known as L'kpralia 

 should remain there until ample living and spirit material of 

 numerous specimens has been examined. 



* Hnime made a genus ChiJopora and Miclielotti called one CJieilopora.. 



Froc. Zool. Soc— 1913, No. XXX.V. 35 



