BIOLOGY. 
Ccel. 17 
duce the same at all levels. In certain embryonic tissues, a usual method 
of development may be acquired, but this is not the case with the germ- 
plasma at all levels. At all the levels the regenerative tissue has a 
tendency to produce preferably certain forms (in Obelia 3-6 or 9-11 
rings). 
In (51) Davenport substitutes a new table for one in (50). 
Garstang (75) finds that Syncoryne sarsii has dimorphic medusae like 
those observed by Agassis in S. mirabilis . 
Grenactier (84) describes the way in which the nematocysts of Hydra 
are discharged. 
Guntiier (88) deals with the anatomy of Limnocnhla tanganyicce in 
detail, and notes a peculiar type of budding, which he believes to be 
primitive. On page 16 is a discussion of the types of freshwater medusae 
hitherto described. 
Gunther (89) has re-examined Limnocodium and olucidatod further 
points in its structure. 
Haller (93) : Histology of the nervous system of Hydra. 
Hargitt (95, 96) : Character and distribution of the genus Perigo- 
nimus. 
Lang (135) reasserts that buds are wholly derived from the ectoderm 
in Hydroids. [See also Braem (26), Seeliger (190).] 
Murbacii (154) : Nematocysts are developed in the proximal regions of 
the body, and then wander to the more distal regions. 
Nutting (161) notes that deep sea Hydrocorallince do not sting as 
much as the shallow water forms, p. 85. 
Nutting (162) describes the asexual reproduction of Plumularia 
pinnata , and suggests the possibility of conjugation among the Plumu - 
lariidm. 
Osborne & Hargitt (166) give an account of a new Hydroid, Perigo- 
nimus jonesii , which possesses many primitive characters, and perhaps 
resembles the ancestor of the calyculate Campanularia , because, though a 
“ naked Hydroid,” it has a covering of slightly compacted slime which 
might, by a slight stiffening, become a hydrotheca like that of the 
Campanularia. 
Seeliger (190) : Budding among Ccelenterata. The eggs are formed 
and migrate independently of the appearance of the budding zone in the 
chief hydranth stalk. In the formation of a budding zone, a disappear- 
ance of endoderm [Lang (135)] does not occur. In both Eudendrium 
and Obelia both layers take part in the formation of the buds. 
Wetzel (210) : Transplantation experiments on Hydra. The speci- 
mens operated on always exhibited an attempt to regain original form. 
Zoja (215) : Ectoderm cells. 
Zoja (216) describes a series of observations on the development of the 
isolated blastomeres of the eggs of some Medusce {Clytia Jlavidula, Laodice 
cruciata , Mitrocoma anna, Liriope mucronata, Geryonia proboscidalis ). 
F 5 
1895. [vol. xxxii.] 
