Mr. W. Clark's Observations on recent Foraminifera. 381 



As to the other organs of 0. Legumen, I coukl only observe in 

 the two or three anterior cells, a dried, perhaps in life, a pulpy 

 mass, apparently inclosed in a membranous sac of a brown co- 

 lour, but in the posterior chambers there were scarcely any traces 

 of this substance, as these apj)eared to be nearly transparent ; 

 it may also be presumed that the membranous sac contains the 

 viscera. 



The constructor of the calcareous cells of 0. Legumen, which 

 communicate with each other by constricted orifices, seems not 

 to be an animal with lobes, deposited in the chambers, or an ag- 

 gregation of polypes linked together, with a common canal for 

 reproduction, sustentation and depuration, but a solitary being 

 produced from a gemma, cast by the parent on a marine substance, 

 which, springing therefrom, constructs the first cell, in which it 

 lives and dies, having previously by gemmation produced its suc- 

 cessor, the architect of the second cell, and so on, until nature 

 has completed the appointed number. 



These inferences arise from the brown membrane, or mantle, 

 or pulp, not being visible in any other than the two or three 

 anterior chambers ; the matters which were originally in the pos- 

 terior, or first cells, probably more hyaline, appear to be lost by 

 collapse and desiccation of the animal. 



I have also removed by acids the calcareous cases of many 

 others of the Eoraminifers, and they have nearly presented the 

 same appearances that have just been stated; from this it would 

 appear that the live polype is only to be found in the last cell, 

 those of the preceding ones having each perished as soon as it 

 had produced the germ of its successor. 



The branchial organs are probably those minute delicate fila- 

 mentary points observed by ]M. Ehrenberg and others, and are 

 perhaps capillary prolongations of the membranous sac or mantle, 

 and serve for the aeration of the circulating fluid as well as for 

 effecting the formation of the calcareous case : that these com- 

 munications with the animal through the foramina have not been 

 discovered in the membrane investing it cannot be a matter of 

 sm-prise, when its minuteness and tenuity are considered, and 

 the examinations being made, if not in a completely dried state, 

 at least in conditions of great collapse. 



These filaments have been considered as spurii pedes, and sub- 

 servient to locomotion ; this idea I shall prove by and by to be 

 erroneous, by showing that the Orthocera, and beyond doubt, 

 some of the Lagena, are fixed to marine substances by a posterior 

 mucronal style ; and I believe that the rest of the Foraminifera, 

 when in their natural habitats, are fixtures. 



The contents of cabinets are composed of detached substances 

 found in coral sand, with their characters usually lost by continual 



