PLYMOUTH MARINE INVERTEBRATE FAUNA. 183 



[ Foraminifera— coH/rf. ] 



Rotalinae. 



Patellina corrugata, AVilliamsou : Williamson, 1858, Rec. For. Gt. 

 Br., p. 46, pi. iii, figs. 86-89. 



Generally distributed, but in small numbers. 



DISCORBINA GLOBULARIS (d'Orbigny) : Williamson, 1858, Eec. For. Gt. 

 Br., p. 53, pi. iv, figs. 104, 105 [as Rotalina concamerata (young)]. 



Cawsand B., at times abundant on the Zostera; [Drake's I. (j.j.L.)]. 

 Generally distributed throughout the district, and in places common. 



DiscORBiXA ROSACEA (d'Orbigny) : Williamson, 1858, liec. For. Gt. Br., 

 p. 54, pi. iv, figs. 109-111 (as Ixotalina mamiUa). 



Cawsand B., very plentiful; Drake's I., and generally distributed. 

 A common species, universally present, and frequently from fifth 

 to sixth of all species in a1)undance. But both Disrorhina glohularis 

 and Discorhina orbicularis appear to merge in this species, and few 

 specimens are so well characterised as Williamson's figure. 



DiscORBiNA ORBICULARIS (Terquem): Brady, 1884, "Challenger" Report, 

 p. 647, pi. Ixxxviii, figs. 4-8. 



Common, and of universal distribution, but less abundant than 

 either of the preceding Discorbime. 



DiscORBiNA PARisiENSis (d'Orbigny): Brady, 1884, "Challenger" Report, 

 p. 648, pi. xc, figs. 5, 6, 9-12. 



Cawsand B., and sparingly represented in most dredgings, but at 

 places apparently scarce. 



DISCORBINA Bertheloti (d'Orbigny): Brady, 1884, "Challenger" Report, 

 p. 650, pi. Ixxxix, figs. 10-12. 

 Much as Discorhiaa parincnsis. 



Planorbulina mediterranensis, d'Orbigny : Williamson, 1858, Rec. 

 For. Gt. Br., p. 57, pi. v, figs. 119, 120 (as P. vulyaris). 



Cawsand B. ; Drake's I., and generally distributed through the 

 district, but in very varying abundance. Sometimes third or fourth 

 in numerical precedence, and sometimes very low indeed. There 

 is no present key to its preferences of locality. 



Truncatulina lobatula (Walker & Jacob): Williamson, 1858, Rec. 

 For. Gt. Br., p. 59, pi. v, figs. 121-123. 



Cawsand B. ; Drake's I., generally distributed throughout the 

 district. Present practically everywhere, but in very varying 

 abundance. Long ago Montagu noted it adherent to Hydroids, 

 and this is the clue to its distribution; wherever Hydroids are 

 present, this is one of the commonest foraminifera. It also exhibits 

 an apparent preference for Scriularella yayi as a host. 



PuLViNULiXA REPANDA (Fichtcl & Moll) : Williamson, 1858, Rec. For. 

 Gt. Br., p. 52, ])1. iv, figs. 101-10;5 [as liotalina concamcnda (mature)]. 

 Cawsand Ji., and generally distributed, but not a species which 

 occurs in abundance. 



PULVINULINA Menardii (d'Orbigny): Brady, 1884, "Challenger" Report, 

 p. 690, pi. ciii, figs. 1, 2. 



Somewhat uncommon, and doubtfully an inliabitant oi the 

 district, but rather a casual visitor. 



