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M. D'Orbigny and the conchologists, as it has entirely separated the 

 Foraminifera from a group with which they had no manner of affi- 

 nity, and brought them down to a much lower position in the zoolo- 

 gical scale. 



At the same time we must remember that the objects hitherto 

 comprehended by naturalists in the group of Bryozoa are all possessed 

 of a comparatively high organization. We find in nearly all of them 

 a well-marked cilio-brachiate polype, having a limited number of lo- 

 calized tentacula, and a digestive cavity furnished with two orifices, 

 serving as mouth and anus : the only exception to this regular form 

 of the polype with which I am acquainted is that of the Cristella- 

 ria, in which the general contour is somewhat different, especially as 

 regards the number and arrangement of its tentacula : but even these 

 are ciliated, and the digestive cavity is furnished with two distinct 

 orifices. ' Professor Rymer Jones observes, " that the existence of 

 ciliae upon the tentacula would seem to be characteristic of the Bryo- 

 zoa, and is invariably accompanied, as far as our information extends 

 at present, with a digestive apparatus of far more complex structure 

 than what we have seen in the unciliated polypes ; for in the class 

 before us, beside the stomach, we find a distinct intestinal tube and 

 anal outlet." — (' General Outline of the Animal Kingdom,' by T. 

 Rymer Jones, F.L.S., p. 108, 1841). Milne-Edwards also, whose re- 

 searches amongst the Bryozoa have so justly rendered him an au- 

 thority on this subject, briefly characterizes his Polypes Bryozoaires 

 as " ayant un bouche et un anus distincts." — (' Elemens de Zoologie.') 

 Even could 1 be satisfied with the applicability, in any instance, of M. 

 Ehrenberg's opinion, which assigns to some of the Foraminifera a 

 localized intestinal canal, within the general sacculated cavity of the 

 organism, still the great Prussian has not attempted to show the pre- 

 sence of either ciliated tentacula or of orifices which could have as- 

 signed to them the separate functions of mouth and anus ; both of 

 which classes of appendages must be demonstrated to exist ere the 

 Foraminifera can be satisfactorily ranked with the true Bryozoa. 



But even in the Rotalina and Rosalince, where the frequent presence 

 of foreign bodies in their interior indicates the existence of a digestive 

 apparatus, there appears to be no portion of the organism specially 

 set apart for the performance of the functions of an intestinal canal ; 

 but the whole interior of the creature, including every articulation, 

 appears to be one common digestive organ, as in the Anwebce and 

 many other Infusoria. In the Polystomellce I have not hitherto been 

 able positively to prove even thus much ; for the only evidence of its 



TRANS. MIC. SOC. VOL. II. P 



