JANUARY 4, 1884.] 
sandstone the remains are not yet destroyed, but 
are in the form of carbon or lignite. In the other 
rocks the vegetable tissue has almost entirely disap- 
peared, and only the impressions remain. The rocks 
are found in blocks or fragments, none of them 
greater than a foot square, scattered along the beach, 
mostly at the base of the bluff, which is composed 
of drift. From our present knowledge, it is not pos- 
sible to decide whether they were torn up from an 
outcrop below high-water mark and cast upon the 
beach, or washed out from the base of the bluff: they 
no doubt belong to the cretaceous, although our 
present proofs are not yet sufficient to state this to 
a certainty. 
A note was read from Dr. Britton of Columbia 
college, in which he stated that the occurrence of 
similar fossiliferous sandstones on the beach near Glen 
Cove, Long Island, and vicinity, had been known for 
some time. There they are found in precisely the 
same position as at Tottenville, and are associated 
with extensive beds of fire-clay, kaoline, etc. The 
Tottenville station is not immediately on these clays, 
but they are found near by in several directions, 
notably at Kreischerville. That the two localities 
mark outcrops of the same geological formation, and 
probably approximately of the same Strata, is almost 
certain. The physical structure of the Glen Cove 
series is exactly parallel to that of certain of the clay 
beds of Middlesex county, N.J., which are well 
known to belong to the cretaceous epoch. In the 
absence of sufficient fossil evidence, we cannot state 
with absolute certainty that the two deposits are 
equivalent; but there is little doubt that this will 
ultimately be proven, and that the New Jersey and 
Staten Island clays, kaolines, lignites, etc., find 
another and their most northern outcrop on the north 
shore of Long Island, at or near Glen Cove. 
The exact parallelism between our Staten Island 
specimens and those from Glen Cove, continued Mr. 
Hollick, can be seen at a glance: in fact, they would 
be indistinguishable but for the labels, with the ex- 
ception of the leafy conglomerate before described, 
which does not seem to be represented elsewhere; it 
is possibly peculiar to Staten Island. 
In determining the genera and species of fossil 
plants, we have to depend mostly upon the veining 
of the leaves, which is not by any means so satisfac- 
tory as we could wish. Genera can be determined 
with comparative accuracy. Thus we have no doubt 
that one of our Tottenville fossils is a willow, though 
what particular species, it is impossible to say; another 
is undoubtedly an evergreen, allied to our juniper or 
arborvitae. The larger specimens are probably wil- 
lows, viburnums, and sour gums. There are also a 
few fragments with parallel veins, —no doubt, belong- 
ing to the grasses, —a small fruit or nut, and a piece 
of what appears to be an equisetum or horse-tail 
rush. These, with other indistinguishable fragments, 
complete our list. 
Cambridge entomological club. 
Dec. 14. — Mrs. A. K. Dimmock showed a collection 
representing stages of thirty-eight species of insects 
SCIENCE. 
25 
which are foung’ upon Betula alba, the white birch, 
which will be given later in Psyche. 
Mr. G. Dimmock showed the two halves of a split 
wing of Attacus cecropia, in which the two layers of 
the wing had been separated by the following mode. 
The wing from a specimen that had never been dried 
is put first into seventy per cent alcohol, then into 
absolute alcohol, and from the latter, after a few days’ 
immersion, into turpentine. After remaining a day 
or two in turpentine, the specimen is plunged sud- 
denly into hot water, when the conversion of the tur- 
pentine into vapor between the two layers of the wings 
so far separates these layers that they can be easily 
. parted and mounted in the usual way as miscroscopi- 
cal preparations on a slide. This is an easy way 
of demonstrating the sac-like nature of the wings of 
insects. 
Dr. H. A. Hagen showed preparations to illustrate 
organs of undetermined function, found on the larvae 
of Gomphidae, Libellulidae, and Aeschnidae, but 
not as yet found on Agrionidae, which he believes to 
be traces of segmentai organs. The organs in ques- 
tion are little cavities or invaginations of the epider- 
mis between the segments, one on each side of the 
median ventral line, on one, two, or three abdominal 
segments, according to the family to which the larva 
belongs. 
Ottawa microscopical society. 
Dec. 18. — Mr. Henry M. Ami read a paper on the 
use of the microscope in determining fossils, with 
especial reference to the Monticuliporidae. Late 
microscopic investigations proved that the more 
minute organisms found in our rocks were both 
deserving and requiring such careful investigations; 
for geologists had been led into erroneous ideas re- 
garding the particular horizon, and range in geologi- 
cal time, of certain species of these fossils from the 
mere cursory examination given them. Later pale- 
ontologists, pursuing their researches in a more 
scientific manner, had recourse to thin sections of 
these Monticuliporidae, or fossil Polyzoa, by means 
of which the true external and internal structures 
of the zoarium or skeleton of the genera and species 
belonging to this family were satisfactorily ascer- 
tained. 
The work of foundation and means devised by Dr. 
Nicholson (at one time a professor in one of our Cana- 
dian universities) inaugurated a new erain the study 
of these interesting forms. The mode of procedure 
in preparing thin sections of these fossils was then 
considered and explained. The different kinds — tan- 
gential, longitudinal, transverse, and axial sections 
— were described, and illustrations of them exhibited 
in charcoal drawings of some of the common species 
- found about Ottawa city, — Prasopora Selwyni Nichol- 
son, Batostoma ottawaense Foord, and Monotrypella 
trentonensis Nicholson; the various points exhibited 
in these sections —such as the large and smaller 
tubes; cystoid, curved, and straight diaphragm or 
floors; the spiniform tubuli, etc. — were then de- 
scribed, showing how minutely and accurately their 
structures and affinities can by this means be detected. 
