May, 1845.] 233 



hence a suture in the cranium is equivalent to the epiphysis be- 

 tween the shaft and head of any one of the long bones.* In the 

 present example, Dr. Morton showed that owing to the total ab- 

 sence of the sagittal suture, the lateral growth of the cranium has 

 ceased at an early period of life ; the presence of the lamdoidal 

 suture has permitted of posterior elongation, and the squamous 

 sutures being entirely open, the upward growth, corresponding to 

 the lines of these sutures, is remarkably developed. 



Dr. Morton expressed his acknowledgments to the Baron Von 

 Gerolt, Prussian Minister at Washington, for the ancient Mexican 

 cranium deposited this evening. It was exhumed from the ce- 

 metery of San Juan de Tlatilolco, near the city of Mexico, in 

 which were buried great numbers of the Mexicans who were 

 slain in defence of their city against the Spaniards, during the in- 

 vasion of Cortez. 



On motion of Prof. Johnson, — .Resolved, That a copy of 

 the Sth vol. of the Journal of the Academy, and a copy of 

 vol. 1st of the Proceedings, and of vol. 2d, as far as published, 

 be presented to the " Museum cTHistoire Naturelle." 



Stated Meeting, May 20th, 1845. 

 Vice President Morton in the Chair. 



A letter was read from Dr. Edward Hallo well, communi- 

 cating some facts observed by him respecting the young of 

 the Opossum, a number of which, with the female, had been 

 recently captured in his neighbourhood. The letter also re- 

 ferred to the practice among the gallinaceous birds of devour- 

 ing serpents, several interesting instances of which were 

 mentioned. 



Prof. Johnson read a portion of the report of his analysis 

 of the specimens of Nile alluvium received from Prof. Lepsius 



•Proceedings, Vol. I, August, 1841. 



