An Early Embryo of Myrmecophaga jubata. 259 
XXIII. An Early Embryo of Myrmecophaga jubata. By Sheina 
M. Marshall, B.Sc., Carnegie Scholar of the University of Glasgow. 
(Communicated by Prof. Graham Kerr.) 
(With Plate and Text-figures.) 
(Read 22nd November 1920. Received 27th November 1920.) 
THE object of this communication is to publish, with short notes, a figure of 
an early embryo of Myrmecophaga, obtained by Professor W. E. Agar in the 
course of his expedition to the Gran Chaco in 1907-1908. 
On the 16th November 1907,a male J. jubata was found by the Indians 
in the forest, and driven into the Mission Station in the Paraguayan Chaco 
about fifty miles due west of Villa Concepcion, and was shot in the station. 
Two days later a female, obviously the mate of the male, was found in the 
same way, and proved to be pregnant. It was accompanied by a young one, 
which is in accordance with the statements that the young accompanies the 
mother till she again becomes pregnant. : 
_ The foetus and placenta were preserved in corrosive acetic. This specimen 
was drawn by Mr Kirkpatrick Maxwell (Plate XXXI.), and was then cut 
into three parts, the middle portion of which contained the embryo. It was 
staimed in bulk with borax carmine, and was sectioned in a _ plane 
approximately transverse to the head region. 
We are practically ignorant of the embryology of that heterogeneous 
set of mammals known as the Edentata, except as regards the Armadilloes 
and the Manidw. No published data regarding the early development of 
any of the Myrmecophagide have been found, consequently any details 
regarding an early embryo of Myrmecophaga are of special interest and 
importance, even when they happen to be such as we should expect from our 
knowledge of the development of other mammals. 
G. Pouchet (Mémoires sur le Grand Fourmilier, Paris, 1874), publishes 
a description and figure of an embryo at a much later stage, when most 
of the adult features are already present. The internal organs, apart from 
the brain and salivary glands, are not described. 
The general appearance of the present specimen (Plate XX XI.) may be said 
to be that of a typical eutherian embryo. It is very like a human embryo 
at the beginning of the second month. G. Phisalix (Archives de Zoologie 
expérimentale et générale, ser. 2, t. vi., 1888) dates at thirty-two days a human 
embryo 10 mm. long cut in the same plane, in which he describes structures 
