512 C. CLIFFORD DOEELL. 



observed previously in the styles of other Lamellibranchs, 

 and I will therefore devote a few words to a description of my 

 observations. 



Out of nine individuals of Circe gibbia Lam. which I 

 examined, five possessed a crystalline style, and three of these 

 were heavily infected with Bacteria — two being- uninfected. 

 The Bacteria all appeared to be of the same species. They 

 were non-motile Yi brio-like organisms of small size, and 

 many dividing forms were present. 



A single individual of Cyreua impressa Desh. Avhich 

 I examined contained a style heavily infected with a 

 Bacillus. 



Seven individuals belonging to the species Psammot^a 

 variegata Wood were found to possess crystalline styles. 

 Five of these contained large numbers of a Bacillus. 



I examined ten specimens of A rca (Scapharca) rhombea 

 Born, and found a style present in six of these. Four out of 

 these six styles were filled with curious branching filaments, 

 whose nature was not determined. I found the same sort of 

 filaments in the style of one specimen of Soletelliusi 

 acuminata. In the living state, the filaments look like 

 fungal grow^ths, and after staining by Griemsa's method they 

 are seen to contain a large nvimber of deeply staining gran- 

 ules. Owing to an unfortunate accident — a heavy thunder- 

 storm which overtook me when I was returning to Trinco- 

 malee with my preparations — my slides of these organisms 

 Avere much damaged, so that I can give no further particulars 

 regarding these peculiar growths. 



The window-pane oyster (Placuna placenta), of which 

 I examined a few specimens, was always found to possess a 

 very long and well-developed style. No parasites were found 

 inhabiting it. Dr. Willey has also examined a number of 

 styles of this mollusc, and always with the sanie negative 

 results. 



I give the results of my examination of the eight species of 

 Lamellibranch referred to iu the followini'- table : 



