408 PRIZE QUESTIONS. 
fusing a strong odor of musk, which is secreted by glands placed near the jaw- 
bones of crocodiles. 
11. An exact anatomical description of the sturgeon, (Accipenser sturio,) with 
a monography of its development from the egg to the adult animal. 
12. A comparison of the remains of castors and emydes found in the peat 
moss, in localities where those animals no longer live, with the living species 
of those animals. 
13. If there be earthquakes which are only attributable to subsidence of 
strata situated at a greater or less depth, by what distinctive characters can 
they be recognized ? 
14. It has been observed that oxygen does not conduct the currents of in- 
duction of the apparatus of Ruhmkorff, except when its tension has been reduced 
to the pressure of 6 mm. of mercury; and that, from that point, its conducting 
power augments, when the diminution of tension is continued until it reaches 
0.5 mm., when its powers appear to have attained a maximum. It is desirable 
that this phenomenon should be confirmed by new experiments, and that, by 
comparing it with what is analogous in regard to other gases, its cause should 
be made known. 
15. New experimental researches on the velocity of propagation of electricity. 
16. A methodical description of the remains of plants of the tertiary forma- 
tion in the Netherlands. 
17. Should metallic masses in a building protected by a lightning conductor 
be placed in communication with the latter or not? On this subject new re- 
searches, both experimental and theoretical, are requested. 
18. A series of new experimental researches on the influence of mechanical 
forces upon chemical actions. 
19. What are the constituent elements of the fatty body in the larve of 
insects, and what are its functions ? 
20. An anatomical description of the Monitor (d¢vittatus) of the island of 
Java. 
21. The Society desires that the corpuscles of the blood in different orders of 
reptiles should be described and delineated after new and original researches. 
22. The density of the vapors of substances is one of their most important 
physical characters ; it is therefore to be regretted that it has as yet only been 
determined with respect to so few inorganic bodies. 'The method indicated by 
M. Sainte-Claire-Deville for that determination seems calculated to extend our 
knowledge upon this point. Hence the Society solicits the determination of 
the density of the vapors of different substances in regard to which that fact has 
remained undetermined till the present time. 
23. Instruments and experimental methods having been sufficiently improved 
of late to enable us to undertake with success experiments on the diffraction of 
sound, the Society requests that those experiments be made, and that there be 
deduced from them a determination of the velocity of sound. 
24. Researches are desired on the modifications in the spectral lines of divers 
substances, produced by different temperatures and densities. 
25. An analytical catalogue (raisonné) is needed of the geographical distri- 
bution of mollusks. 
The ordinary prize for a satisfactory answer to each of these questions is a 
gold medal of the value of 150 florins, and a further gratuity of 150 florins if 
the answer is deemed worthy thereof. The answers, legibly written in Dutch, 
French, English, Italian, Latin or German, (Roman letters,) and free of charge, 
with billets in the manner usually adopted in like cases, must be addressed to 
Professor E. H. Von BaunnavsEr, Perpetual Secretary of the Holland Society 
of Sciences, at Harlem. 
