268 



HARDWICKE'S SCIENCE-GOSSIF. 



as regards size and definiteness of structure. Ordi- 

 narily, the shell is transparent and colourless, egg- 

 shaped, with the narrow end truncated by the mouth ; 

 but in some of the larger ones the lower end is pro- 

 longed, when it appears somewhat flask-shaped. 

 These larger forms I have not yet been able to find, 

 but in these, according to Professor Leidy, " the shell 

 is clearly seen to be composed of regular plates, of 

 nearly equal size, of oval form, arranged alternately 

 in longitudinal rows and overlapping at their con- 

 tiguous borders. This arrangement produces the 

 impression of hexagonal areas defined by zones of 

 smaller elliptical areas" (see Fig. 215). In the 

 smaller forms, which I have procured in abundance 

 from among mosses and Algae in several of our 



Fie. i\i,.—Englypha aheolata. Specimen showing sarcode 

 retracted, and test with apparent diamond-shaped workings. 



Fig. 215. — Ditto, pseudo- 

 podia extended. 



Fig. 216. — Specimen of ditto 

 with four spines ; pseudo- 

 podia extended. 



wells, the structure is not, by any means, so clearly 

 defined ; indeed, in the majority of individuals, the 

 structure of the shell is very obscure, and, when 

 seen at all, frequently appears only as fine, diamond- 

 shaped markings. Some specimens show from two 

 to six thorn-like spines of about equal length, attached 

 to the shell near the fundus or top ; in others these 

 appear to have been rubbed off. The sarcode is 

 generally colourless, though sometimes yellowish or 

 brown, occupying most of the shell, though often 

 constricted in the middle, in an hourglass manner, as 

 in Figs. 2 1 4, 2 1 5 and 216. Nucleus large, situated near 

 ihe fundus. The size of this species, like that of most 

 Rhizopods, varies considerably ; my specimens ave- 

 raged about 355 or ,i^ of an inch in length, but the 



larger forms from Sphagnum are as much as thcxon of 

 an inch in length. 



Fig. 214. Specimen with sarcode retracted, show- 

 ing hourglass-like contraction : test with diamond- 

 shaped markings. 



Fig. 215. Prettily-marked form, pseudopodia ex- 

 tended. 



Fig. 216. Another, with hourglass-like contraction 

 of sarcode ; pseudopodia extended ; with four spines. 



Ejiglypha ciliata is exclusively of sphagnous habitat. 

 It very closely resembles E. aheolata, but the shell is 

 more compressed, and has a fringe of hairs or spines 

 round the top and sides. These spines vary consider- 

 ably, not only in numbers, but also in length and 

 strength, and in the amount of surface they cover. 

 In most other respects it is identical with E. alveolata. 



Fig. 217. Empty colourless test, structure obscure, 

 but indicating overlapping plates. 



Fig. 218. Another specimen, with finer and more 

 numerous spines, covering nearly the whole surface. 

 Trinema euchelys is one of the smallest, and also 



■:v\Jji!U^a-A 



mmMm- 



Fig. 217. — Euglypha ciliata. 



Fig. 218. — Ditto, another 

 specimen. 



one of the commonest, of the testaceous Rhizopods. 

 It is a rare thing to find a pond or ditch which will 

 not furnish specimens of this ubiquitous animal. In 

 squeezings from Sphagnum I have procured them in 

 thousands, and, according to the authority previously 

 quoted, " it is often found in the earth about the 

 roots of mosses and other plants, even in such places 

 as roadsides, on the bark of trees, old wooden or 

 thatched roofs, and in the crevices of pavements of 

 cities." The shell is transparent, colourless and 

 pouch-like, with the oral end generally the smallest. 

 The mouth is circular, sub-terminal and inverted. In 

 a front or back view, the shell of ordinary specimens 

 is more or less ovoid, of homogeneous, chitinoid 

 membrane ; but in the larger forms, from sphagnous 

 swamps, the shell is made up of circular plates with 

 beaded borders. The large, handsome varieties I 

 have been unable to procure, the nearest approach 

 being an empty shell, from Sphagnum, with delicate 

 punctations arranged in circles on the shell. Fig, 222. 

 Although not a striking form, yet the glassy shell is 

 beautiful from the elegance of its curves, A nucleus 



