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and viewed by transmitted light. Where the tubes approach each 

 septum retrally, we find that this tuberculated structure is very evident, 

 particularly in the external depressions or " fossettes " of D'Orbigny, 

 where the tubercles are very large, (fig. 3, d and 4,f,g)* forming 

 an irregular row running parallel to the septum. Some authors 

 appear to have mistaken these for a series of large foramina. 



On removing the calcareous shell, by means of hydrochloric acid, 

 I found that the soft animal body occupying the compartments was 

 very curious (fig. 6 and 7). The anterior surface of each segment was 

 convex (fig. 7, a), the posterior concave (fig. 7, b). From the two 

 lateral margins of each segment there projected, retrally, a row 

 of small obtuse processes, which, when in situ, obviously occupied 

 the internal grooves and their terminating tubes (fig. 4, a and d). The 

 inner arch of perforations (fig. 5, b) was occupied by a series of small 

 connecting necks, which united the segments one to another (fig. 6, b 

 and 7, d), and apparently formed exceedingly minute channels of com- 

 munication between one chamber and another. Sometimes these 

 tubes appeared to be constricted in the middle, as if half strangulated 

 in passing through the narrow orifice in the calcareous septum. 



This soft animal consisted of a very thin external membrane 

 filled with a gelatinous matter; being analogous in this respect to 

 what I had observed in Rosalina and other forms of Foraminifera. 

 Dried specimens of Polystomellce obtained from the British coast, 

 have never afforded me any instances of these internal portions 

 after being de-calcified, — a few minute shreds constituting all that 

 was left. From my Falmouth examples, however, I readily ob- 

 tained them, and found them to be translucent, and of a brownish 

 colour. On drying the latter, previous to attempting to mount them 

 in Canada balsam, I found that the evaporation of their contained 

 fluid led to the total loss of all definite form and outline, leaving 

 little more than a vague and unmeaning yellowish stain upon the 

 glass. Scores of attempts only furnished me with one example which 

 even approached success. This shows the extreme tenuity of the 

 membrane and the fluid nature of its contents. After trying the same 

 experiment upon a great number of individuals from near the Island 

 of Tenedos and the Castles of Europe, in the Dardanelles, I was at last 

 successful in obtaining a few beautiful specimens, from one of which 

 the sketch (fig. 6) was taken. In these the membrane was more 



* The latter figure, which is drawn from a specimen mounted in Canada balsam, 

 shows the rounded bases of these tubercles shining through the shell. 



