SCIENTIFIC SUMMARY. 
209 
and of the Hamilton and Genesee-Shale divisions of the Devonian in Canada 
and the United States. In a paper read before the Geological Society 
(March 12, 1879) that gentleman described a great number of forms of 
these bodies, including most of those figured by Pander from Russian 
Silurian rocks, and some not previously met with. In the Chazy beds they 
are associated with numerous Entomostracan Crustacea of the genus Leper- 
ditia, a few trilobites, and some gasteropods ; in the Cincinnati group they 
occur with various fossils ; and in the Devonian principally with fish- 
remains ; but none of the associated fossils furnish any clue to the true 
nature of these problematical bodies. Mr. Hinde regards their zoological 
relationship as very doubtful, but they most resemble the teeth of Myxinoid 
fishes. 
Fossil Remains of Annelids. — At the same meeting of the Geological 
Society Mr. Hinde described numerous jaws of annelids which he had 
obtained from Cambro-Silurian, Silurian, and Devonian rocks in Canada, 
and from the Lower Carboniferous of Scotland. The existence of annelids 
during the deposition of the older rocks has hitherto been evidenced chiefly 
by the occurrence of their trails, and of a few impressions of their bodies ; 
the former being a very uncertain ground, seeing that in some cases, at any 
rate, the supposed annelid-trails have been proved to be the tracks of crus- 
taceans. Of the nature of the fossils described by Mr. Hinde, chiefly ob- 
tained from shallow water deposits, no doubt could be entertained; he 
showed their close resemblance to the jaws of existing annelids, and indeed 
was enabled from these resemblances to refer them to well-known families. 
Mr. Hinde enumerated fifty-five different forms of these minute bodies, 
mostly from the Cincinnati group of Canada ; and classified them under seven 
genera, five belonging to the family Eunicea, one to the Lycoridea, and one 
to the Glycerea. 
MICROSCOPY. 
Method of Investigating the Embryos of Fishes. — M. Henneguy has com- 
municated to the Philomathic Society of Paris the description of a method 
of preparing the embryos of fishes and other similar objects for microscopic 
purposes. He places the ovum for a few minutes in a 1 per cent, solution of 
osmic acid until it acquires a light brown tint, and then in a small vessel 
containing Muller’s liquid, in which he opens it with fine scissors, when the 
central vitelline mass dissolves at once in the fluid, and the solidified germ 
can be extracted from the ovum for examination. By treating the germ with a 
solution of methyle-green and then with glycerine he has been able to observe 
in the cells of segmentation those very delicate phenomena which have been 
lately described by Auerbach, Biitschli, Strasburger, Hertwig, and others, 
proving that the treatment to which the ovum had been subjected did not 
alter the elements of the germ. 
For the purpose of making cross-sections of the embryos, M. Henneguy 
leaves them for some days in Muller’s liquid, and colours them with picrocar- 
minate of ammonia. He then treats them with alcohol of spec. grav. 0*828, 
and afterwards with absolute alcohol to free them from water, and soaks 
NEW SERIES, YOL. III. NO. X. P 
