88 PKOCEEDINGS OP THE NATIONAL MUSEUM yol. 72 



In the Smittinidae and the Reteporidae, the operculum does not 

 close the ovicell and there are no oral avicularia present, but in these 

 two families there are oral glands. 



We have always supposed that the zooecial avicularia have a phys- 

 iologic function when they are constant. This new study completely 

 confirms this supposition. But we do not yet know exactly how this 

 function is exercised and if it is always the same. 



We may again note how fruitful the physiologic classification is 

 and how great are the results obtained by its use. Thanks to it, these 

 small animals have already revealed many secrets of their complicated 

 biology. 



BUFFONELLARIA DIVERGENS Smitt, 1873 



Plate 8, Figures 7, 8; text Figure 13a 



1873. Hippothoa divergens typica Smitt, Floridan Bryozoa. Kongl. Svenska 

 Vetenskaps-Akademiens Handlingar, vol. 11, no. 4, p. 47, pi. 9, 

 fig. 179. 



7,^ . . . J^a = 0.09 mm. 



Measurements. — Aperturel , ^ , r. ^ - r^ 



Ua = 0.10-0.12 mm. 



„ . [is = 0.65 mm. 

 ^^^""Mz. = 0.45-0.55 mm. 

 Structure. — The ovicell is very fragile, placed on the distal zooecium, 

 and opened very widely above the operculum and without any rela- 

 tionship with it. It is smooth and convex. 

 The operculum is suborbicular with two 

 lucidae at the place of the condyles of artic- 

 ^ ulation; the two muscular attachments 



Tig. 13.-0PERCUI.A of buffonell- ^re removed from the margin and placed 

 AEiA. ^.B. DIVERGENS Smitt, 1873. rather high. 

 ^.B.KETicuLATA, NEW SPECIES rj.^^ f^^^^^j^ ^^^^ ^^ trauspareucy, 



shows the radial threads characteristic of Buffonellaria. This struc- 

 ture is very different from that of Hippothoa and can not be con- 

 fused with it. There is generally only a small oral avicularium. 



Affinities. — It is in error that Hincks, 1880, Norman, 1909, and 

 Osburn, 1914, have referred this species to StepJianosella hiaperta 

 Michelin, 1848. Not only it has not the same form of operculum, 

 but the structure of the ovicell is very different; finally, the frontal 

 is an olocyst with nerve-like threads and not a tremocyst with small 

 pores. We have not found specimens corresponding to Smitt's Figure 

 177 (forma laxa). 



Biology. — Our specimens encrust Cellepores, hydroids, and corals. 

 They were in reproduction in May, 1884, and January, 1885. This 

 species has been found only in deep waters. 



