CXCil GENERAL SUMMARY OF SCIENTIFIC AND 



for the larvae or pupae, have been the subject of curious ex- 

 periments. Forel, 'on soiling and deforming the silken co- 

 coons containing the pupse, always found the next morning 

 that the ants had restored them to their original form and 

 primitive whiteness. Hiiber spoke of the precision with which 

 a column of ants moved, and the perfect order the army ob- 

 served on a long march. Forel, however, shows that this 

 precision would be impossible unless the ants were careful to 

 preserve order. An ant carrying a heavy cocoon, wholly 

 taken up with its burden, is incapable of giving attention to 

 any thing else. Some wander, while others, better assured of 

 their course, <ro straight on. After much hesitation the wan- 

 derers again find the road, as shown by the readiness with 

 which they march on. This is regarded by Forel as an evi- 

 dence of an excellent memory. 



Forel also studied the power of reproduction in the work- 

 ers. It is known that they sometimes lay eggs. He has 

 shown that by their whole structure such individuals are 

 intermediate between the fecundated females and the work- 

 ers or neuters. Their ovaries are sometimes completely, 

 sometimes only partially, developed. 



He also affords a number of new observations on the arch- 

 itecture of these creatures. He finds that the nests of the 

 same species sometimes vary in their interiors. Forel doubts 

 whether certain ants live in the nests of others, as if parasitic. 

 He finds that two kinds of ants lodged in the same nest oc- 

 cupy separate apartments, with walls separating them. Fo- 

 rel has studied better than any one else the habits of the iso- 

 lated fecundated females. He has studied and created alli- 

 ances between the industrious species and those incapable of 

 rearing their young ; he has watched their battles, and also 

 noted the influence of temperature and of light on the move- 

 ments of the ants; 



The functions of the anterior pair of ganglia, or so-called 

 brain, of a water-beetle {Dytiscus marginalis) have been 

 studied by Faivre. He believes that these ganglia preside 

 especially over the movements of deglutition ; that they de- 

 termine not only the contraction but the dilatation of the 

 pharyngeal sphincter-muscle, which reacts at the same time 

 Hirith the recurrent on the cardiac sphincter. The power pe^ 

 culiar to this nerve-centre can be set in play by impressions 



