ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
713 
rapidly, the tail-fold soon becomes very thin, and the general behaviour 
is much more like that of the larvae of Hana. 
Egg and Larvae of Teleosteans.*— Mr. E. W. L. Holt has a report on 
a series of observations carried on during the Royal Dublin Society’s 
Survey of Irish Fishing-grounds. Twenty species were identified and 
nine not. The ova of Lepadogaster bimaculatus are attached to the 
shell by numerous interlacing fibrils which form, by the cohesion of 
their distal ends a structure resembling a shallow circular basket with 
a thickened rim, from which are given off numerous fine filaments of 
considerable length. In Trachinus vipera it was observed that the 
pectoral and pelvic fins were connected by a narrow lateral ridge which 
may, as Balfour suggested for Elasmobranchs, be regarded as a con- 
tinuous lateral fin. For the first time the larva of the Dragonet ( Calli - 
onymus lyra ) has been hatched out from the egg, and the author gives a 
detailed description of it. With regard to a very conspicuous egg of an 
unknown species the author notes that it was only found in compara- 
tively open water. 
Development of Ganglia in the Fowl.t — Herr M. Goldberg finds, in 
sections of embryos of the second day’s incubation, a strand of cells dorsal 
to the medullary canal, and connected with the ectoderm. This strand is 
derived from the ectoderm, has a secondary connection with the medul- 
lary canal, and gives origin to the ganglia of the trunk, to most of 
those in the head, and also to the peripheral nerve-ganglia. Goldberg 
confirms the observations of Onodi, Loewe, and others as to the origin 
of the spinal ganglia. In the head, the Gasserian, ciliary, acoustic, 
petrosum, jugular, and nodosum develope as the spinal ganglia do ; while 
the genicular, the optic, and the olfactory ganglia develope directly 
from the brain. As to the origin of the sympathetic ganglia, Onodi’s 
observations are confirmed. 
Development of the Genital System4 — Dr. J. Janosik has made a 
study of this question ; he comes to the conclusion that if all the parts 
of the generative system were fully developed in Mammals (inclusive of 
Man) and the Fowl, a hermaphrodite gland would result ; in this the 
testis would be internal, and the ovary superficial, as in lower animals 
where such relations have been described. 
Primitively a gland is formed in which the only epithelial elements 
are those of the primary proliferation ; if the secondary proliferation is 
weakened or suppressed, the gonad becomes a testis, but if it increases 
considerably an ovary arises. It follows that the cells from which the 
sperm is formed are descendants of the cells which arise from the 
primitive proliferation of the germinal epithelium, and are, therefore, 
ontogenetically older. 
Phenomena of Fertilization^ — Prof. F. Vejdovsky points out that 
Fol is mistaken in saying that the “ centrokinetic theory ” was discovered 
by E. van Beneden and Boveri. In his memoir on BhyncJielmis, first 
published, in Bohemian, in 1887, but deposited in MS. in November 
* Scientific Trans. Roy. Dublin Soc., iv. (1891) pp. 435-74 (6 pis.), 
t Archiv f. Mikr. Anat., xxxvii. (1891) pp. 587-602 (1 pi.). 
t SB. K. Akad. Wiss. Wien, xcix. (1890) pp. 260-88 (1 pi.). 
§ Anat. Anzeig., vi. (1891) pp. 370-75. 
1891. 3 E 
