ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
329 
found in the same place, even when the young are one and a half mm. 
long. The cell-rows, however, are ordinairly covered by epidermal cells, 
with which they have not the least connection. 
Although the author agrees with Wilson in believing that row T. 
(of Wilson’s nomenclature) passes into the ventral ganglionic chain, he 
does not find that the development of that apparatus is as simple as is 
ordinarly stated. A plexus of nerve-cells is developed along the middle 
ventral line long before the cells of the “ neural row ” develope into 
nervous elements. These ventral cells are ordinarly uni- or bipolar. 
The author is of opinion that these nervous cells have a different genetic 
history from the neural cells, and that they arise from ordinary ecto- 
dermal cells, 
The author traces briefly the history of the other rows, and 
expresses a hope that he will soon be able to publish his results in 
detail. 
Anatomy of Earthworms.* — The more important points in Mr. F. E. 
Beddard’s paper, in addition to the description of three new species 
of AcantJiodrilus — A. antarcticus, A. Bosse, A. Balei — and of one new 
Perichseta — P. intermedia — appear to be the following : — 
He describes the ciliation of the spermathccal appendix in A. Bosse, 
and the presence in Eudrilus of two pairs of ovaries connected by ovi- 
ducts with a single aperture on either side ; these oviducts are continuous 
with the ovaries. P. intermedia differs from most species of Perichseta 
in having a single pair of nephridia in each segment, and in having a 
tubular atrium like that of Acanihodi ilus ; it has also functional egg-sacs, 
wherein the ova undergo their development surrounded by a follicular 
epithelium, and with a mass of germinal cells attached to one pole, as in 
some members of the “ limicolous ” division of the Oligochcnta. Pm- 
chseta is provided with a peripheral nerve-plexus which is specially deve- 
loped in the neighbourhood of the setae ; AcantJiodrilus has a subintestinal, 
and Perichseta and Thamnodrilus a subneural blood-vessel. 
An account is given of the minute structure of the spermathec^ and 
the spermathecal appendices in Perichseta and Acanihodrilus ; spermatozoa 
are only found in the appendices, the epithelium of which has largely 
undergone degeneration into a viscous substance, in which the sperma- 
tozoa are imbedded. The former of these two genera has epidermic 
glands, which are, possibly, equivalent to the capsulogenous glands of 
Lumhricus ; and both of these possess organs which probably corresj^ond 
to the so-called pericardial glands of Lumbriculus ; they consist of a 
network of capillaries with numerous spherical dilatations which are 
crowded with cells. The whole network forms a compact series of organs 
clothed with chloragogen cells, which, though limited to the anterior 
segments, exhibit a more or less perfect metameric arrangement. Special 
glycogenic organs appear to exist in Ac. georgianus in the form of a series 
of paired sacs attached to the septa. 
The Rings of Piscicola.t— Hr, S. Apathy has reinvestigated the 
relation of rings to somites in Piscicola jpiscium. That there are three 
rings to a somite is an old error; that there are a dozen was the 
♦ Quart. Juurn. Micr. Sci., xxx. (1890) pp. 421-79 (2 pis.), 
t Zool. Anzeig , xii. (1889) pp. (349-52. 
