SEPTEMBER 17, 1897. ] 
form the transverse Ductus buvieri, but 
joins instead the great hepatic vein (Ductus 
arantii) not far from the heart. 
(3) Allantoic Vili. The stalk of the Al- 
lantois begins to form onits cephalad side 
within the abdomena series of lobulated 
outgrowths, which gradually increase until 
they occupy a relatively considerable space 
in the abdomen. These villi consist of a 
cuboidal mesothelium covering a mass of 
matricial or ground substance, in which are 
scattered a few cells of mesenchymal char- 
acter. The villiare beginning their devel- 
opment in embryos of 14.0-17.0 mm., and 
are already reduced in embryo of 24.0 mm. 
The author has no surmise to offer as to 
their function. Nothing similar to them is 
known in other mammals. 
(11) Harvard Embryological Collection. By 
Dr. Caries SEpewick Mrvot, Read- 
ville, Mass. 
The collection consists mainly of se- 
ries of sections of vertebrate embryos. 
It is expected ultimately to have repre- 
sentatives of several divisions of the 
Mammalia, and of the principle types of 
non-Mammalian vertebrates. 
The work of forming the collection is 
going forward with the following forms : 
Man Necturus 
Dog Amia 
Pig Amiurus 
Rabbit Batrachus 
Chick Acanthias 
Lacerta Torpedo 
Frog Petromyzon 
Amblystoma Amphyoxus 
The plan is to select for each form a care- 
fully graduated series of stages, and to make 
of each stage three complete series of sec- 
tions in three planes, the transverse, the 
sagittal and the frontal, or if the embryo is 
curved or twisted the three planes are 
chosen at right angles to one another. A 
drawing of each stage is made. A double 
SCIENCE. 
435 
catalogue is kept; the first, in book form, is 
the entry-catalogue, and records all details 
of preservation, cutting, staining and 
mounting. Theseries of sections are num- 
bered according to their order of entry. 
The second catalogue is on cards, which are 
arranged first according to species, second 
under each species according to stage. 
Every series of sections has a separate 
entry number and a separate card. Every 
section is counted and the sections of every 
series numbered. At the present time there 
are about one hundred series completed. 
The collection is intended primarily for | 
investigators, and is open to all competent 
investigators working in the Embryological 
Laboratory. It is hoped that it will in- 
erease during years to come, in size and 
still more in usefulness. So far as known 
to the writer, it is the first collection of the 
kind to be started. 
(12) Organic Selection. By Prorrssor H. 
F. Ossorn, Columbia University, and 
Proressor H. B. Poutton, Oxford Uni- 
versity. Duplicate title (see No. 25). 
(14) Characters for Distinguishing the North 
American Species of Oeresa. By Wm. H. 
AsHMEAD, United States National Mu- 
seum, Washington, D. C. 
An explanation of the application of re- 
cently discovered morphological characters 
to the classification of the Homopterous 
genus Ceresa. The author points out the 
fact that many of the genera in the Mem- 
bracidee are merely dimorphic forms of other 
genera. 
(23) Reconstruction of Phenacodus primevus, 
the most Primitive Ungulate. By PROFESSOR 
Heyry F. Ossorn, Columbia University, 
New York. 
This paper is accompanied by the re- 
mounted skeleton of Phenacodus and a wax 
model executed by Charles Knight. As orig- 
inally mounted in Professor Cope’s labora- 
tory, the famous skeleton of Phenacodus pri- 
