184 Scientific Intelligence* Zoology. 
observer^ in the Transactions of the Academy of Sciences of 
Modena, has a memoir on the contractibility of vegetables. He 
communicates some experiments, from which he infers, that the 
phenomenon of contractibility observed in different parts of plants, 
and which Tournefort considered as a mechanical effect of elas- 
ticity, must be viewed as a consequence of vitality. Thus the 
contraction of the valves in the seed-vessels of balsams, when 
the seeds are ripe, may be considered as an example of thispower. 
If such capsules are immersed in laurel water, which kills their 
vitality, they lose their contractile power, while, if put into cold 
water, their contractile power remains unchanged. 
ZOOLOGY. 
18. Note regarding the Spider whose W eh is employed in Me-- 
dicine, hy N M. Hentz. — ^It has lately been discovered, that the 
web of a species of spider, common in caves in Pennsylvania, 
possesses a narcotic power ; and it has been administered with 
success in the treatment of certain fevers. This spider, of which 
M. Hentz has figured a large female, with a description of the 
parts of the mouth, and the disposition of the eyes, belongs to 
the genus 'Fegenaria of M. Walckenaer, or to that of Aranea^ 
properly so called, of M. Latreille. M. Hentz proposes to give 
it the specific name of I\ medicinalis. It is black, tinged with 
blue, and its abdomen presents about ten pale and livid spots, 
as well as a line, toward its anterior extremity. In some indi- 
viduals, the legs are marked with black spots. The author is 
of opinion that the webs of ail the species of the same genus in 
America are equally narcotic. It would be interesting to make 
some experiments upon those of the European spiders, with the 
view of determining whether they possess the same property. — 
Journal Acad. Nat. Sciences of Philadelphia^ vol, ii. 
19. Notice regarding the Breeding of the Peacoch Parrot erf 
South AmericcL — The author of this notice having put together, 
at Paris, in the month of April 1822, two peacock parrots, male 
and female, obtained an egg on the 18th May following ; three 
days after a second ; then a third and a fourth, with the same 
interval as that observed between the laying of the first and 
second. Two of these eggs were found to be clear ; and the 
other two, when broken by M. Gabriac, after an incubation of 
