KONGL. ÖV. VET. AKADEMlliN.s IJANULINGAR. BANU. 19. N:0 4. 91 



being more or less loosely connected, whence ai-ises tlie differeiicc iii tlie nuiiiber of 

 visible apertures; not iinfrequently the shell appears as it' brokeii througli by the im- 

 raense apertures, wliicli look like large defects in the ehamber-walls. The shape of 

 the chainbers varies from globifonn and oval to coinpressed thuiub-like and even beak- 

 formed. 



The surface of tlie shell and the size of the pores are also liable to soruc va- 

 riation, but even such featiires seeni in this species to be only of an accidental 

 character. 



The niost distinet eharacter is found in the variety called Gloh. hirsuta d'Orbigny, 

 which has its clianibers regularly coiled up in a nautiloid way, with the last ones 

 generally unattached to the preceding coil. The aperture in this variety is sitnatcd on 

 the inner (or lower) side of the last chaniber. It is a inediate form betweeii the pig- 

 my and the typical forms. Notwithstanding all such peculiar features, we do not con- 

 sider it in aecordance with the usual conception of varietal distinction to mark this 

 form with a separate designation. 



The thick-walled, sometimes very coarse form with several outer apertures, by 

 d'Orb. distinguished as Gloh. ruhru, is one of the commonest on our bottoms and has 

 usually a reddish tint. 



Mr. H. Bkady in his valuable paper »Notes on same of the Reticulavlnri Rhizopoda 

 of tlie ^'Ghallenger» Expedition» in Quart. Journ. Microscop. Science (new ser.) 75, p. 284. 

 distinguishes the following varieties of Globigerina bulloides: 



Globigerina duhia Egger. 



» cretacea d'Orb. 



1) cequilateralis d'Orb. 



» digitata Bråd. 



n infläta d'Orb. 



" Dutertrei d'Orb. 



» i'ubra d'Orb. 



» conglobata Bråd. 

 sacculifera Bråd. 



» 



» helicina d'Orb. 



Fig. 195: a form near to Reuss' and others' Glob. trilobatii, with the chainbers 

 highly developed from the tirst .md with 1 or 2 apertures; seldom met with on the 

 coralline-gravel. 



Fig. 196: a coarse, thickshelled form with large chambers and several apertures; 

 it conjes near to Glob. rubnt. d'Orb. and may be identical with Glo!>. conglobata Bråd.; 

 from the coralline-gravel. 



Figg. 197 — 199: with large and loosely connected chambers, large apertures, and 

 with the last chanjber approaching to the thund^form. The pores are of middle size 

 sunk in the bottom of the usual hexagonal im|)ressions (iig. 199); from the coraliine- 



