Xx Proceedings of the Association of American Anatomists 
members of lower races whose language is of the simplest kind; of study- 
ing the relations of the insula to the lenticular nucleus, claustrum, and 
the mass of the paraclaustral lamina of white fibres; and lastly, of 
obtaining the brains of left-handed persons for the purpose of seeking a 
commensurate redundancy of the right insula as compared with the left. 
THE DISTRIBUTION OF BLOOD VESSELS IN THE LABYRINTH OF 
THE EAR OF THE DOMESTIC PIG. By GEorGE E. SHAMBAUGH. 
Hull Laboratory of Anatomy, University of Chicago. 
(Read by title.) 
The circulation of the labyrinth of the pig’s ear was studied by means 
of celloidin casts of the labyrinth. Injections of a large number of 
embryos were made, of sizes measuring from 2.5 em. in length to the 
foetus at full term. The complicated system of vessels found in the 
foetus at full term was interpreted in part by the study of the more 
simple arrangement found in the younger embryos. The arterial blood 
is supplied to the labyrinth by a single vessel which reaches the laby- 
rinth through the meatus acousticus internus. Its terminal branches 
anastomose freely with each other before giving off the vessels which 
supply the various parts. The venous blood is collected in a single 
large trunk which leaves the labyrinth along with the canaliculus 
cochleae. 
A. COMPARISON OF HUMAN AND ORANG HEARTS, WITH LANTERN 
SLIDES. By J. Ratru Harris. Washington, D. C. 
(Read by title.) 
SINUSES OR AIR CHAMBERS IN COMMUNICATION WITH THE NASAL 
FOSSAE. By DanieEL KERFoot SHUTE. Columbian University, Wash- 
ington, D.C. 
NOTES ON THE EARLY DEVELOPMENT OF RODENTS. By Tuomas G. 
LEE. University of Minnesota. 
Spermophilus tridecemlineatus exhibits in its preplacental develop- 
ment certain remarkable and important conditions which differ from 
those of any other marumal yet described. The ovum enters the uterine 
cavity in the morula stage usually surrounded by a zona pellucida; it 
rapidly differentiates an ectodermal trophoblast layer and an inner cell 
mass which forms the germinal ectoderm and endoderm. The uterus has 
a characteristic T-shaped lumen, the lateral portion or placental chamber 
next the mesometrium, the vertical portion consisting of the long inter- 
mediate portion which terminates in the fixation chamber at the an- 
timesometrial portion. 
