ie AMERICAN MIDLAND NATURALIST 
one.- I refer to a small treatise by Albertus Magnus, the eminent 
professor of St. Thomas Aquinas. It is entitled De Secretis Mulie- 
rum item de Virtutibus Herbarum, Lapidum et Animalium, etc. 
Bound in the same volume is a similar treatise, De Secretis Naturae, © 
by Michael Scotus. In the latter are found nearly the same dis- 
cussions, though with important modifications as the quotations 
show. In spite of our want of appreciation of theories of the 
thirteenth century, a theory of the twentieth is not a jot more 
useful, true, or important unless based more solidly on facts. 
The following quotations from the aforesaid works of Albertus 
and Scotus may in any case prove of interest. 
“Et nota secundum Avicennam, si semen cadit in latere 
sinestro matricis, generatur foemella, si in dextro, generatur 
masculus.’’* ‘Et ideo in dextro generantur masculi, etc, etc.’’7 
It will be noted too that this theory of sex-determination is 
attributed by Albertus to the Arabian philosopher, Avicenna. 
Whenever quotation is made due credit is always given by the 
ancient scientists, but gives examples of observed facts when he 
makes a modification in this old theory. Compare the following 
from Michael Scotus. 
“In latere dextro dicimus quod masculus concipitur and 
in sinistro foemina, ut quidam volunt: nos vero dicimus quod 
latus non facit ex !toto, sed semen testiculi, quia de dextro, exit 
masculus, and de ‘sinistro foemina, etc. etc.” 
Then follows a practical observation and proof for what he 
says. 
Scotus beside this devotes two chapters to the subject of 
sex-determination. (Chaps. XVI., XVII.), Albertus also has a 
special chapter VIII. on the subject. Scotus intimates that there 
have been exceptions to the theory.§ 
That there are some ideas on sex-determination which can 
hardly be viewed by us as anything but absurd maybe admitted, 
but in view of the striking similarity of the views expressed in 
these quotations with those of Mrs. Calhoun and professor Jordan, 
we are justified in “believing that were the scientists of to-day 
better acqpainted with the works of the distant past less time 
would be lost in rediscovering things old. 
* Abertus Magnus. L. C. p. 96. Compare also p. 103. 
TF JS OS. Te Cie 
§ Scotus, M. De Secretis Naturae. pp. 266, 267. 
