214 
THE VOYAGE OF H.M.S. CHALLENGER. 
Globigenna sacculifera, Brady. 
„ xquilateralis, Brady. 
„ conglohata, Brady. 
,, dubia, Egger. 
,, I'ubra, d’Orbigny. 
,, bulloides, d’Orbigny. 
„ injlata, d’Orbigny. 
,, digitata, Brady. 
„ cretacea, d’Orbigny (?). 
„ dutertrei, Brady. 
OrbuUna universa, d’Orbigny. 
Hastigeiina pelagica (d’Orbigny). 
Pullenia obliquiloculata, Parker and J ones. 
Sphaeroidina dehiscens, Parker and Jones. 
Candeina nitida, d’Orbigny. 
Cymbalopora { Tretomphalus) bulloides 
(d’Orbigny). 
Pulvinulina menardii (d’Orbigny). ‘ 
,, tumida, Brady. 
„ canariensis (d’Orbigny). 
„ micheliniana (d’Orbigny). 
„ crassa (d’Orbigny). 
The majority of these species are limited to those deposits immediately nnder warm 
tropical waters, while only a few of them are met with in deposits from the colder regions 
of the ocean ; it follows that the predominating species in a deposit vary according to 
latitude, or more correctly according as the surface oceanic currents have a tropical or 
polar origin, along with other surface conditions of the locality. 
The colour of the deposit is white, milky-yellow, rose, brown, or greyish, depending 
on the nature of the inorganic substances mixed up with the Foraminifera. The pre- 
vailing colour is milky-white or rose-coloured far from land, and dirty white, blue, or 
grey near land, when there is a considerable quantity of detrital matter from rivers in 
the deposit. It has sometimes a mottled aspect from the presence of manganese grains 
or volcanic ashes, lapilli, and fragments of pumice. It is fine grained and homogeneous ; 
in tropical regions many of the Foraminifera are visible to the naked eye, while in 
temperate regions the form of the organisms is, as a rule, indistinguishable without the 
aid of a lens. When dried a Globigerina Ooze is usually pulverulent, but some specimens 
which have a low percentage of carbonate of lime cohere slightly. 
In the Tables of Chapter II. there are 118 samples of deposits described as Globi- 
gerina Ooze. These come from depths ranging from 400 to 2925 fathoms. In addition 
to these there are a few doubtful cases where a Globigerina Ooze was indicated. 
3 .samples come from depths of less than 
2 
13 
35 
49 
„ between 
}} f> 
ft 
tf * V 
500 
500 and 1000 
1000 „ 1500 
1500 „ 2000 
2000 „ 2500 
fathoms. 
IG 
over 2500 fathoms. 
The average depth of the above samples is 2002 fathoms ; taking the doubtful samples 
into account, the average depth would be 1996 fathoms, and excluding those samples 
