592 REPORT OF COMMI«SIONER OF FISH AND FISHERIES. 



the Flagdlata^ and the Tintinna xwnow^ the Ciliata. Both groups, aud 

 partictilaily the Jsoctilucidce^ belong" to the neritic phmktoii. They occur 

 in the oceanic only where the coast water Hows in (G, pp. (iTO, 750, 033). 



The common yoctiluca miliaris and some related species sometimes 

 cover the surface of the coast waters in such masses as to form a thick 

 reddish-yellow slime, often like "tomato soup," and at night are 

 brightly luminous. The Tintinnoidw ( Tintinniis, Dicfyocyafa, CodoncUa) 

 appear in smaller quantities, but ofteu in great numbers. Some forms 

 of these elegant Ciliata are oceanic. 



Thalamophora {Foraminifera). — The Thalamopliora, often and very 

 I)roperly called Foraminifera, were once generally regarded as ben- 

 thonic. New observations first showed that a part of these are plauk- 

 tonic, and through the comprehensive series of observations by the- 

 Challenger the abundant occurrence of these pelagic Foraminifera and 

 their great part in the formation of that most important sediment, the 

 Glohigerina ooze, was first established. All these Thalamophora of the 

 plankton belong to the peculiar perforated Polythalaniia, to the family 

 of the Glohigerinidcc; only Orhulina (provided it is independent) to the 

 Monoihalamia. The number of their genera (8-10) aud species (20-25) 

 is relativelj^ small, but the number of individuals is inconceivably 

 great. By far the most important aud numerous belong to the genera 

 Glohigerina. Orhulina^ and Pulvimdina ; after these Sphwroidina aud 

 Pullenia. They occur everywhere in the open ocean in numberless 

 myriads. J. Murray could often from a boat scoop up thick masses of 

 them with a glass, and never fished with the tow net in 200 fiithoms 

 without obtaining some (5, p. 534). A few forms {Hastigerina and 

 Cy)nhalopora) show more local increase in numbers, while others are 

 rare everywhere {Chilostomella, Gandeina). In the equatorial counter- 

 currents of the Western Pacific, between the equator and the Caroline 

 Islands, the Challenger fouud "great banks of pelagic foraminifera. 

 On on(^ day an unheard-of quantity of Fulvinulina was taken in the 

 tow nets; on the following day they were entirely absent, and Fnl- 

 lenia Avas extraordinarily abundant.'' These important observations 

 by ]\Iurray I can confirm from my own experience in the Atlantic and 

 Indian oceans* (comp. 3, pp. 106, 188). 



*Thc iniportaut relatitms of thcKo pelafj,ic rolythalamia to the rest of the fauna of 

 the plankton on the one side, as well as its importance in the formation of the "(llobi- 

 gerina ooze" on the other, has hccn expressly stated by Murray (6, p. 919). I agree 

 completely with him in the view that these oceauie (ilohi<jtrhiid(C uro true pelagic 

 rhizopods, whic-h in jiart art; found swinniung only at the surface or at slight deptlis 

 (autopelagic), in part at zones of dilferent depths (zonary), but they are not ben- 

 thonic. The enormous Ke<liment of "Globigvrhia ooze" is eomi)Osed of the sunken 

 calcareous shells of the dead ))elagic animals. On the other hand, the benthonic 

 thalamopliores, living partly abyssal, on the bottom of the dee]) sea, i)artly littor.al, 

 creeping among the forests of seaweed on the coasts, are of other species and geiiern. 

 They develop a much greater variety of form. The neritic thalamopliores found 

 swimming in the const waters are in \y.\rt agniu cliaracterized by various forms. 



