116 J. J. LISTER. 



like second chamber. The central and second chambers of the 

 parent shell are represented as exactly resembling in size and 

 shape those of the young. 



In 1884, Brady's magnificent monograph (1 a) on the 

 Foraminifera appeared in the " Challenger " Reports. The 

 work deals mainly with the classification and distribution of 

 the Foraminifera, their life-history being little noticed. There 

 are, however, two records in it which bear upon the matter. 



A specimen of Gristellaria crepidula (Fight, and Moll, sp.) 

 is described and figured (Plate 68, figs. 1 and 2), which con- 

 tained young shells in three of the terminal chambers. The 

 parent shell is megalospheric, the megalosphere being pear- 

 shaped, and measuring 110 x 84 /i. The young shells consist of 

 a spherical or somewhat triangular chamber varying in size 

 from 60 to 30 /i, to which in some cases a second smaller 

 chamber is added. 



In the description of Cymbalopora (Tretomphalus) bulloides, 

 d'Orb., in which the shell of small chambers, arranged in an 

 irregular spiral, is completed by an enormously inflated terminal 

 chamber, it is stated, on the authority of Dr John Murray 

 (p. 639), that in every specimen from the surface which was 

 examined, " the shell was filled with minute monadiform 

 bodies." 



In a paper (26) published in 1885, Munier-Chalmas and 

 ScHLUMBERGER introduced the terms Megasphere and Micro- 

 sphere for the central chambers of the two forms of a species. 



In October, 1888, Brady (2) described specimens of Orhito- 

 lites coniplanata, Lamk., var. laciniata, Brady, collected in Fiji, 

 whose large peripheral chambers were crowded with young 

 megalospheric individuals. Such specimens had been pre- 

 viously recorded by W. K. Parker. 



In Brady's specimens the parent form was microspheric. 

 Vertical and horizontal sections of the shell are figured, 

 showing the small chambers continued to the centre. It is 

 pointed out that these shells differ from those whose centre is 

 occupied by a primitive disc (the megalospheric forms, cf. fig. 

 45), not only in the absence of the primitive disc, but in the 



