PRIZE QUESTIONS OF SCIENTIFIC SOCIETIES. 
In accordance with a request from Utrecht, we give the following 
translation of the proceedings of several of the Holland societies, 
relative to prize questions proposed by these establishments for free 
competition to the- citizens of all nations. We regret that we have 
not received a full set of these proceedings, but hope to present in a 
future report the remainder of the series. — Sec. Sm. Inst . 
EXTRACT FROM THE PROCEEDINGS OF THE HOLLAND SOCIETY OF SCIENCE 
AT HARLEM, FOR THE YEAR 1856. 
The society held its 104th annual session on the 17th of May, 1856. 
Since its last session it has received: 1st. A memoir, written in Ger- 
man, and having the epigraph, “Wee aspera ter rent.” This memoir 
w T as written as a reply to the following question : 
“A history is requested of the development of the Peiromyzon fluvi- 
atilis , illustrated by the necessary figures, and compared with that of 
’•other fishes, according to the researches of Yon Baer, Rathke, and 
C. Vogt.” 
This memoir does not, in fact, contain the history of the Petro- 
myzon jluviatilis , but that of P. Planeri. However, this latter species 
is so i ear akin to the other, that the memoir substantially answers the 
purpose proposed for it by the society, and the gold medal is therefore 
awarded to the author, Dr. Max Sigmund Schultze, doctor of medi- 
cine and philosophy, and^ professor extraordinary of anatomy in the 
University of Halle. 
The society has received: 2dly. A memoir, written in German, 
bearing the epigraph, ^Amicus Plato , amicus Socrates , sed magis 
arnica veritas” and relative to the following question published by 
the society: 
“The illustrious director of the University of Pulkowa, the As- 
tronomer F. G. W. Struve, published in 1847 his well-known book, 
entitled “Studies in Stellar Astronomy.” In that work he com- 
municates, as the result of his observations, some very remarkable 
details concerning the structure of the universe and the transparency 
of space. The London Astronomical Society, in its report of the' 
twenty-eighth general meeting, gave the support of its authority to 
Struve 7 s results, while, on the other hand, the celebrated astronomer 
J. F. Encke, in No. 622 of the Astronomische Naehrichten , considers 
them hypothetical and without foundation. The society, conse- 
quently, desires that a profound and scrupulous examination may 
