288 Royal Society : — 



congenial home, and attain their greatest development, at great 

 depths, the general rule has seemed to be that Foraminifera are pro- 

 gressively dwarfed in proportion to increase of depth, as tliey are 

 by a change from a warmer to a colder climate — those which are 

 brought up from great depths in the Equatorial region bearing a 

 much stronger resemblance to those of the colder temperate, or even 

 of the Arctic seas, than to the littoral forms of their own region. 



The author then refers to the recent researches of Prof. Huxley 

 upon the indefinite protoplasmic expansion which he nRxnesBathi/fjius, 

 and which seems to extend itself over the ocean-bottom under great 

 varieties of depth and temperature, as among the most important of 

 the results obtained by the sounding-apparatus. 



By the recent extension of dredging-operations, however, to depths 

 previously considered beyond their reach, very important additions 

 have been made to the Foraminiferal fauna of the Deep Sea. 

 Several new generic types have been discovered, and new and re- 

 markable varieties of types previously known have presented them- 

 selves. It is not a little curious that all the tiew types belong to 

 the Family Lituolida (consisting of Foraminifera which do not 

 form a calcareous shell, but construct a " test" by the agglutination 

 of sand-grains), which was first constituted as a distinct group in 

 the author's 'Introduction to the Study of the Foraminifera' (18G2). 

 The first set of specimens described seem referable to the genus 

 Proteonina of Prof. Williamson ; but the test, instead of being com- 

 posed (as in his specimens) of sand-grains, is constructed of sponge- 

 spicules, cemented together with great regularity, so as to form 

 tubes, which are either fusiform or cylindrical, being in the former 

 case usually more or less curved, and in the latter generally straight. 

 Of the genus Trochammina (Parker and Jones) many examples were 

 found of considerable size, resembling Nodosarians in their free 

 moniliform growth, but having their tests constructed of saud-grains 

 very firmly cemented together, with an intermixture of fragments of 

 sponge-spicules, which give a hispid character to the surface. — The 

 genus Rhabdammina of Prof. Sars is based on a species (the R. abys- 

 soruin) first obtained in his son's dredgings, of which the test is 

 very regularly triradiate, sometimes quadriradiate, and is composed 

 of sand-grains very regularly arranged, and firmly united by a ferru- 

 ginous cement. Not only was this type represented by numerous 

 specimens in the ' Lightning' dredgings, but another yet more con- 

 siderable collection was formed of irregularly radiating and branching 

 tubes, which are composed of an admixture of sand-grains and 

 sponge-spicules, united by ferruginous cement. These seem to 

 originate in a " ])rimordial chamber" of the same material, which 

 extends itself into a tube that afterwards branches indefinitely. 

 This tyj)e may be designated R. irreyiiiaris. — Of the i)rotean genus 

 Lituola (Lamarck) a large form was met with wliich bears a strong 

 resemblance to the L. Soldani of the Sienna Tertiaries. Its nearly 

 cylindrical test is composed of sand-grains very loosely aggregated 

 together, forming a thick wall ; and its cavitv is divided by si'pta 

 of the same material into a succession of chaiiibtTs, arranged in 



