L52 SUMMARY OF CURRENT RESEARCHES RELATING TO 



light. It seems that the chemical constitution does not change, but 

 thai one and the same class of substances serves to maintain the animal. 

 In Vertebrates the glycogen is first consumed and then the fats, but it 

 is not so in the medusa where there is no appreciable selective use of 

 different substances. The dried weight is about J '76 p.c. of the living 

 weight, and this ratio does not change as the animal starves. 



In the starving animal the cells become reduced in size, many 

 degenerate and disappear ; the cell-boundaries tend to become indistinct. 

 The gelatinous substance becomes vacuolated and the muscular tonus 

 is largely lost. The bell-rim bends upward and inward in a balloon-like 

 manner. The mouths on the mouth-arms disappear in about three 

 weeks, so that even if there were nannoplankton present it could not 

 be used. 



Porifera. 



Sponges of Lake Baikal.* — Xelson Annandale finds that some of 

 the Baikal sponges are Haploscleridae, namely the genus LubomirsTzia 

 Dybowski in the sub-family Chalininae and Baikalospongia g.n. in the 

 sub-family Renierinse. The new genus includes forms like Lubomirskia 

 in general structure, but friable (though hard) and not at all elastic. A 

 stout basal membrane of a horny nature is present. The skeleton 

 superficially resembles that of Lubomirskia, except that there is no 

 horny sheath to the fibres, and that the vertical fibres do not form 

 definite brush-like tufts at their distal extremity, but are more or less 

 distinctly splayed out to form a horizontal skeletal reticulation. There 

 are no true microscleres. Gemmules have been found in one species- 

 ovoid or pear-shaped structures with a simple horny covering which is 

 distinctly depressed in a craterif orm manner at the narrower end. They 

 He in the stout basal membrane of the sponge with their long axis 

 parallel to it. The embryos, which are often abundant in Baikalospongia 

 bacilli/era, resembles those of Lubomirskia, but the free-swimming larva 

 is unknown. 



There are also true Spongillidas in Lake Baikal, remarkable for the 

 abnormal character of their microscleres. There can be no doubt that 

 the species of Lubomirskia are of marine origin. Indeed one of them, 

 L. baikalensis, has actually been found in Behring's Straits. Although 

 the affinities of Baikalospongia are doubtful, it seems probable that its 

 species are derived from a marine stock. 



New Sponges. t — F. Ferrer proposes a new family of Sigmatophora 

 (Ectyonillidte) including Ectijoailla g.n. (with protriaenes, with anat- 

 rigenes, with an axinellid type of skeleton, without microscleres), 

 Cantabrina g.n. (without protriaenes, with anatriaenes, with an axinellid 

 type of skeleton, without microscleres), and a number of known genera 

 — Raspailia Nardo, Dktyocylindrus Bow., Cyamon Gray, and Trikentrion 

 Ehlers. 



* Records Indian Museum, x. (1914) pp. 137-48 (1 pi.). 

 + Boll. Soc. Espanola, Hist Nat., xiv. (1914) pp. 451-5. 



