On the so-called Biogen Liquid. 399 
Some time previous to the date of my discovery, I learned that 
the nebular hypothesis .had been abandoned by some of its most 
distinguished advocates in consequence of the revelations of Lord 
Rosse’s telescope. ‘This fact, together with several other conside- 
rations, prevented me from at once making the result of my in- 
vestigations public. Having, however, again and again revised 
my calculations, and having found that according to the theory 
of probabilities there are many millions of chances to one against 
the accidental coincidence of so many independent variable quan- 
tities, I ventured to submit the subject to the inspection of as- —— 
tronomers. ‘The interest it appears to have excited, and the favor. — 
with which it has been received, have exceeded my most enthu- 
Siastic anticipations. If it be indeed the expression of a physical 
law and not a mere harmony; it undoubtedly opens to men of 
science a vast field for cultivation. . 
Arr. XXXIX.—On the so-called Biogen Liquid ; by Cuar.es 
traRD, Member of the Boston Natural History Society. 
Tue following pages are devoted to an examination of a letter 
published in the American Journal of Science and Arts,* also of 
a communication read before the Boston Natural History So- 
ety in December, 1848.+ poe wt 
The letter consisted of an exposé of three facts and one the- 
ory, Viz. : 
First fact. The formation of the egg in the ovary, as observed 
in a soft-shelled mollusk (Ascidia) and in a worm (Sigalion). 
econd fact. 'The germinative vesicle does not always and 
necessarily disappear before the division of the yolk. 1 
Third fact. There exists in the centre of the germinative 
spot, a transparent vesicle. 
heory. What embryologists have called albumen in the egg 
of invertebrated animals, has nothing in common with the albu- 
men of the egg of Vertebrata. This liquid is the mother liquid 
of the yolk, that is to say, of the elements from which a new 
individual originates; therefore it is called Biogen. 
These facts which have been added to science were not first 
made known by Mr. Desor. The theory is really his own. We 
shall presently see on what it rests. are : 
n the communication read before the Boston Natural History 
Society, besides a brief account of the letter just mentioned, we 
find introduced some comparisons between certain pretended phe- 
nomena which are said to take place in the earlier age of the egg 
and the merely conjectural phenomena of the nebular hypothesis. 
bE 
* Second Series, vol. vi, No. 21, (May, 1849,) p. 395. 
+ See Journal of that Society, vol. iii, p. 85. 
