CHAHA. 1 1 



large numbers uniformly scattered through, the rock-mass, and 

 (ii) their occurrence in strata formed in water of considerable 

 depth. 



The generic name Calcuphmra was proposed by "Williamson ' for 

 certain small bodies common in Carboniferous Limestone rocks in 

 the neighbourhood of Moel, North Wales ; this name is applied to 

 the American fossils by Knowlton with the specific designation 

 C. Lemoni, Xnowl. 



From the same geological horizon Dawson* has described what 

 he regarded as a foraminiferal species, Saccammma {Calcisphcsra) 

 M-iana, Daws., and these, Brady suggested, probably belong to the 

 same group as the forms figured by Knowlton. Dawson's figures 

 are not nearly so suggestive of Chora, as are those of Knowlton. 

 Since Dawson named these Devonian fossils, Ulrich,' in ignorance 

 apparently of previous descriptions, instituted a new foraminiferal 

 genus, MoeUerina, for their reception. From the Carboniferous 

 Limestone of Gloucestershire Wethered* has recorded another form, 

 which he places in Williamson's genus Calcisphmra, but with the 

 belief that it is of a Protozoan nature. Enough has been said to 

 show the possibility of our having to go back to Devonian strata 

 for the earliest specimens of Chara. Without having seen 

 Xnowlton's material, and being aware of the difficulties pointed 

 out by experienced specialists, it must be admitted that the figured 

 specimens exhibit a very marked resemblance to Characeous fruits : 

 the reasons brought forward against accepting this resemblance as 

 proof of identity do not appear by any means decisive. The number 

 of enveloping cells need not be regarded as fixed and unalterable, 

 and a similar occurrence of large numbers of Charas in the rook 

 matrix may be noted in the case of the Paris Basin fresh-water 

 rocks of Eocene age. In most cases the plants are represented by 

 the so-called "fruits," which are simply the oospores enclosed in 

 the spirally arranged cells of the envelope, or, not infrequently, 

 without the encasing cells. Remains of the vegetative organs are 

 rare, and such as have been described in a fossil state are of little 

 or no interest from a botanical point of view. 



1 Phil. Trans. 1880, p. 521. 



' Canad. Nat. n.s. vol. x. p. 1. 



^ Geol. Mag. 1886, n.s. Dec. 3, vol. iii. p. 374. 



* Quart. Joum. Geol. Soc. vol. xliv. Proc. p. 91. 



