) regarding the future determination of sex. Must we accept the view of Empedocles of Trinacria that the right ovary (the postmenstrual period, assert others) is responsible for the birth of males or are the too long neglected spermatozoa or nemasperms the differentiating factors or is it, as most embryologists incline to opine, such as Culpepper, Spallanzani, Blumenbach, Lusk, Hertwig, Leopold and Valenti, a mixture of both. This would be tantamount to a cooperation (one of nature’s favourite devices) between the nisus formativus of the nemasperm on the one hand and on the other a happily chosen position, succubitus felix , of the passive element. The other problem raised by the same inquirer is scarcely less vital: infant mortality. It is interesting because, as he pertinently remarks, we are all born in the same way but we all die in different ways. Mr M. Mulligan ( Hyg. et Eug. Doc.