532 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Perichsetae from the Eastern Archipelago.* * * § — Mr. F. E. Beddard 
and Miss S. N. Fedarb describe some new species of Perichseta from the 
East, which were collected by Mr. Everett some months ago. These 
new species of the genus come from Borneo and Palawan. In addition 
to these Mr. Everett found Pontoscolex corethrurus and Megascolex armatus, 
both of which are widely distributed forms. 
Breeding Habits of Earthworms.t — Mr. E. A. Andrews has made 
a study of the small earthworm Allolobophora foetida, and finds that it 
conjugates beneath the surface and cannot therefore be directly observed. 
Momentary immersion in boiling corrosive sublimate preserves the con- 
jugating individuals in the natural position, and a study of this shows 
that the process is essentially the same as in Lumbricus, but the union 
is much firmer and more intimate. We may hold that the spermato- 
phores in terrestrial Oligochaetes are not of the importance they are 
elsewhere, but that they are to a large extent accidental results of 
secretions taking place during conjugation. 
Enchytrseidae-j:— Prof* J. Nusbaum finds that the nuclei which Ude 
described on the walls of the heart-like swellings of Enchytraeidae are 
true cells, as may be well seen in some species of Fridericia. They are 
bound to the wall, but move backwards and forwards in the blood stream, 
and probably correspond to blood cells. As Ude noted, no free blood 
Cells are known. Nusbaum confirms R. Hesse's observation that the 
blood sinus, from which the dorsal vessel arises, and which Michaelsen 
regarded as a cleft between the wall of the gut and the muscular layer, 
has in Fridericia Patzelii , &c., a very distinct lining epithelium. The 
so-called “ heart-body ” in the dorsal vessel of some Enchytraeidae (e. g. 
Mesenchytrseus ) is probably of the same nature as the above-mentioned 
blood cells. The author describes Fridericia oligosetosa sp. n. and 
F, bichseta sp. n. (subspecies typica), and compares them with other 
forms. 
Ganglia of the Ventral Nerve-chain of Leeches. § — MM. C. Simon 
and G. Thiry have re-investigated this subject, which has been dis- 
cussed by so many previous writers, because they find that the ideas of 
these various authors vary so much among themselves. The recent 
methods of staining nerve-fibres have been of considerable assistance to 
them in their studies. In the face of the very divergent statements 
which have been made by their predecessors, they find it difficult to 
speak with confidence on many points. Two, however, they regard as 
well established. There are fibres which arise from the commissures and 
traverse the ganglion without stopping in it. These fibres pass out by 
the posterior commissure. Other fibres curve outwards to pass out 
by the lateral nerves. The authors enter at length into a detailed account 
of the somewhat complicated course taken by the nerve-fibres. One 
matter of interest may be mentioned. Between the points of emergence 
and the lateral nerves there are two multipolar cells, one dorsal and the 
other ventral. The constituents are placed in such a way that one of 
* Ann. and Mag. Nat. Hist., xvi. (1895) pp. 69-73. 
t Johns Hopkins Univ. Circ., xiv. (1895) p. 74. 
X Biol. Centralbl., xv. (1895) pp. 25-31. 
§ Journ. Anat. et Physiol., xxxi. (1895) pp. 237-49 (1 pi.). 
