ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
45 
which form the coelom sac. Perhaps it is the sparsity of yolk which 
has made Paludina more primitive than the other Gastropods which 
show primitive mesoblasts at an early stage, even before gastrulation. 
Musculature of Chiton.* * * § — Miss L. Y. Sampson first describes the 
muscles of the shell: — (1) A median dorsal muscle; (2) a pair of 
oblique dorsal muscles; (3) a series of longitudinal lateral muscles 
from the dorsal surface of the apophyses to the ventral surface of the 
next piece in front. The muscles of the foot — latero-pedal, medio- 
pedal, postero-oblique, &c. are then described, as are, finally, those of 
the mantle. 
Solenogastres.j — Herr J. Thiele gives an account of some of the 
Solenogastres of Naples, — Neomenia grandis sp. n., Proneomenia (Amphi- 
menia) neapolitana Thiele, Proneomenia vagans Kow. u. Mar., Bhopalo- 
menia aglaophenise Kow. u. Mar., Ph. Eisigi sp. n Myzomenia banyulensis 
Pruvot. He suggests the advisability of placing those genera which have 
a slightly developed cuticular layer in a special family (Myzomeniidae) 
between Neomeniidae s. str. and the Chaetodermatidae. He gives a useful 
general account of the comparative anatomy of the Solenogastres. The 
generalized type of nervous system consists of a supra-oesophageal 
ganglion, the centre for the oral cirri ; two lateral longitudinal stems 
united posteriorly above the rectum ; two ventral stems, united to one 
another and to the laterals by numerous connectives, and also connected 
with the supra-oesophageal ganglion ; an oesophageal ring with which 
are associated two small buccal ganglia, the centre for the anterior part 
of the gut. Pharynx, oesophagus, radula and glands form the true 
stomodseum, lined by epithelium without cilia. The radula is fre- 
quently without a basal membrane, which is remarkable. Only the 
cloaca is truly proctodaeum, the rectum is endodermic. 
Arthropoda. 
Insect Fauna of Rhode Island Coalfield, i — Mr. S. H. Sc udder de- 
scribes Anthracomartus , the first Arachnid discovered in the Carboniferous 
deposits of the Eastern United States, a new genus of Neuropteroidea 
and one of Protophasmida, allied to certain French forms, and presenting 
new features of alliance between the Carboniferous faunae of Europe and 
America. A number of cockroaches, represented by wings alone, show 
considerable variety of form. 
a. Insecta. 
Sub-intestinal Nervous System of Insects.§— M. A. Binet has suc- 
ceeded, by a special method of double staining, in following the course 
of the nerve-fibres of the cylinder-axis, into the protoplasm ; here he 
finds that the fibres do not enter into relation with the muscles, but that 
in certain cells they remain united into a bundle, and describe a spiral 
turn around the nucleus before separating ; in other nerve-cells the 
fibrils separate regularly from one another as soon as they have pene- 
trated into the cell, and describe spiral lines in the more superficial 
layers of the protoplasm. 
* Jenaische Zeitschr. f. Naturwiss., xxviii. (1894) pp. 459-68 (4 figs.), 
t Zeitschr. f. wiss. Zool., lviii. (1894) pp. 222-302 (3 figs.), 
t Bull. U.S. Geol. Survey, No. 101 (1893) 21 pp. (2 pis.). 
§ Journ. Anat. et Physiol., xxx. (1894) pp. 449-580 (4 pis.). 
