384 THE MICROSCOrE. 



lion. One globular species appears like a specimen of tlio 

 Chinese ball-cutting — one sphere within another ; but it 

 is of a marked and distinct kind. 



"The shells of some of the globnlar forms of these 

 Polj'cystina, whose conjugation I believe I have witnessed, 

 are composed of a fine fretwork, with one or more large 

 circular holes ; and I suspect the junction to take place 

 by the union of two such apertures. That the figures of 

 these shells become elongated, lose their globular form 

 after death, and present a disturbed surface is seen in 

 some of the figures represented near the bottom part of 

 Plate III." Major Owen proposes to make Orhulina a 

 subgenus of Glohigerina. The internal chambers of the 

 former are in form remarkably like those of the latter, 

 and like them also they present themselves with varying 

 surfaces, some free from, while others are covered with^ 

 spines. Those without internal chambers have been 

 known as Orhulina universa, fig. 78, Plate III. while 

 figs. 75 and 76, although members of the same family, 

 have been separated ; but he wishes to see all united under 

 the name of " Glohigerina universa" 



The minute siliceous shells of Pohjcydina present won- 

 derful beauty and variety of form ; all are more or less 

 perforated, and often prolonged into spines or other pro- 

 jections, through which the sarcode body extends itself 

 into pseudopodial prolongations resembling those of Acti- 

 nophiys. When seen besporting themselves in all their 

 living splendour, their brilliancy of colouring, says Major 

 Owen, "renders them objects of unusual attraction." Wo 

 have endeavoured to give some idea of the colour of tho 

 living forms in Plate 111. Nos. 43 to 52. The same ob- 

 Berver believes that they wish to avoid the light, " as they 

 are rarely found on the surface of the sea in the daytime ; 

 it is after sunset, and durmg the first part of the night 

 especially, that they make their appearance." 



The Polycyslina appear to have most affinity with tho 

 Foramivifera. Thirty four genera and about two hundred 

 nnd ninety species have been described. They are most 

 abundant in the fossil state ; .and are very phnitiful in tho 

 rocks of Bermuda, in the tripoli of Pichmond, Virginia, in 

 the marls of ISicily, and other places. Their minute shells 



