MarcH 22, 1912] 
The following communication from a member of 
the society was received by the secretary too late 
for presentation at the Princeton meeting: 
A Peculiar Structure in the Embryo of the Honey 
Bee: Jas. A. Neuson, U. 8. Department of 
Agriculture. 
In embryos from fertilized eggs of the honey 
bee, at the time when the germ layers are forming, 
but before the lateral folds have begun to unite, a 
small lenticular mass appears on the dorsal side of 
the egg, close to the cephalic pole. Its outer sur- 
face is almost plane, its inner strongly convex and 
studded with numerous delicate processes which 
join with the protoplasmic meshwork of the in- 
terior of the egg. This mass, which will be termed 
provisionally the cephalo-dorsal disk, appears to 
be a syncitium, composed of rather clear and 
vacuolated cytoplasm, within the inner half of 
which numerous nuclei are embedded. It lies at 
the surface of the egg and is continuous at its 
edges with the surrounding blastoderm. This 
structure was first noticed in 1904 by O. Dickel, 
who called it the ‘‘yolk plug.’’ Dickel identified 
the point in the blastoderm where it first appeared 
as the blastopore, described the disk as formed by 
the migration of yolk cells to this point, and sought 
to connect it with the rudiments of the mesenteron, 
in an endeavor to interpret the process as gastru- 
lation. A study of the antero-dorsal disk in sec- 
tions of eggs of various ages shows: (1) that the 
so-called yolk plug does not arise from yolk cells, 
but from the blastoderm of the dorsal side of the 
egg by a cephalad migration of its cells and their 
aggregation at this point; (2) that at no time 
has the cephalo-dorsal disk any connection with the 
rudiments of the mid-intestine; (3) that during 
the stages immediately following the formation of 
the germ layers it becomes broken up into ame- 
boid cells which wander off into the yolk at the 
cephalic end of the embryo. It therefore appears 
to be a center of distribution for cells from the 
blastoderm to the yolk. Its homologies are ob- 
secure, although Hirschler (1908) has described a 
somewhat similar structure which he called the 
‘‘dorsal organ,’’ in the egg of the chrysomelid 
beetle Donacia. It is also interesting to note that 
the cephalo-dorsal disk has, in its position, time of 
appearance and structure a very close resemblance 
to the cell mass described by Petrunkewitsch in 
the drone egg as derived from the polar bodies and 
later forming the male sex cells. 
The following exhibits were made during the 
meeting of the society: 
SCIENCE 
475 
An Early Human Cranium: H. H. WiuDER, Smith 
College. 
Microscopical Preparations of Epithelium of Pla- 
thelminths: R. T. YouNG, University of North 
Dakota. 
Microscopical Preparations to Show Amitosis in 
the Testis of Tenia serrata: R. T. YounG, Uni- 
versity of North Dakota. 
JOHN H. GEROULD, 
Secretary 
DARTMOUTH COLLEGE 
THE AMERICAN INSTITUTE OF CHEMICAL 
ENGINEERS 
THE fourth annual meeting of the American 
Institute of Chemical Engineers was held in Wash- 
ington, D. C., December 20-23. 
The reports of the various officers for the year 
were read, and a very gratifying growth in mem- 
bership was shown. New officers for the year were 
elected as follows: 
President—Dr. L. H. Baekeland. Second Vice- 
president—Dr. T. B. Wagner. Third Vice-presi- 
dent—Professor M. C. Whitaker; the first vice- 
president being Dr. Eugene Haanel. Treasurer— 
Dr. F. W. Frerichs. Secretary—Dr. John C. 
Olsen. Auditor—Mr. G. W. Thompson. Directors 
—Messrs. A. C. Langmuir, H. S. Miner and A. 
Bement. 
The following papers were read at the Wednes- 
day morning session: 
‘“‘The Hardening of Plasters and Cements and 
a Simple Chronographie Apparatus for Recording 
Set,’’ Dr. Chas. F. McKenna. A very ingenious 
as well as simple instrument for measuring and 
recording this important property of cements was 
shown and explained by Dr. McKenna. 
‘¢Advances in Testing Explosives,’’ Clarence 
Hall. 
‘¢Distribution of Power in Portland Cement 
Manufacture,’’ Richard K. Meade. 
‘¢Problems in the Manufacture of C.P. Acids,’’ 
J. T. Baker. 
“¢Combustion of Pulverized Coal,’’ L. S. Hughes. 
‘«Manufacture of Gelatin,’’ Ludwig Thiele. 
During the afternoon the institute visited the 
Bureau of Standards and inspected the standard- 
ization of weights and measures, adjustment of 
pyrometers, thermometers, pressure gauges and 
similar instruments, as well as the liquid air ap- 
paratus. Every one was impressed by the very 
excellent work being done by this important gov- 
ernment bureau. 
