938 KECOKD OF CUERENT EESEARCHES RELATING TO 



5 per cent., and wlien a mixture of 20 parts peptone and 20 parts 

 honey was employed, the bees refused their food altogether, and most 

 of them died. A mixture was made of 1-18 parts glutinous peptone, 

 100 parts sugar, and 60 parts rose-water ; it was all eaten, but neither 

 honey or wax produced ; the bodies of the bees were distended, their 

 honey-bags full, but their stomachs empty. A mixture of 342 grams 

 sugar-syrup and 28 grams egg-albumen was also quickly consumed, 

 but no honey or wax obtained. A similar mixture of egg-yolk (24 to 

 414 sugar-syrup), produced a small proportion of wax only. 



As general results, the authors believe that the food of bees should 

 not be highly nitrogenous, and that beeswax is formed from non- 

 nitrogenous substances, especially sugar. Erlenmeyer is further of 

 opinion that the fatty portions of the bees' bodies are formed solely 

 from hydrocarbons, the albumenoids only playing the part of nourish- 

 ment to the active organs, keeping them in working order and 

 supplying waste. 



Scent-organs of the Male Privet Hawkmoth.*— Herr W. von 

 Eeichenau, as already briefly reported,! following up Dr. Fritz Miiller's 

 discoveries in this direction, finds both the j^rivet and pine hawk- 

 moths to be provided, in the imago state, with a special scent-organ 

 at the edge of the lower side of the first abdominal segment ; it comes 

 into view on pressure of the abdomen of the dead or living insect, and 

 consists of two symmetrical bunches of hair-shaped scales, which may 

 be extruded or drawn in. "When they are extruded in a living Sphinx 

 Uijustri, a distinct musky scent is apparent at the distance of half a 

 metre ; but ceases when they are retracted into their fold, which 

 occurs when the insect is at rest. In minute structure they are really 

 capillary tubes, tapering gradually to points, and filled with globules 

 of the scent substance ; they do not spring simply from depressions in 

 the chitinous skeleton, as do the ordinary scales, but are rooted in, 

 and radiate from, a sac common to them all ; this sac contains an 

 opaque white mass, and is capable of being stretched by two muscles 

 attached to the ends ; in it the hairs stand close together, united by a 

 long band of tissue, and each implanted by a pincer-shaped root. 



The parts probably act as follows: — The moth, when excited, acts by 

 its nervous system on the muscles of the segmental fold, so that they 

 open the latter, transforming it into a boat-shaj)ed groove ; at the 

 same time the muscles of the base of the hairs exercise a tension upon 

 the band which unites the bases of these, and causes them to become 

 arranged as a radiating, instead of a converging group ; when these 

 muscles cease to act, the hairs converge again and retreat into the 

 fold. The muscles also act by stretching the basal sac, so that its 

 white contents are pressed against the roots of the hairs, and entering 

 them, expel some of the contained scent material through the tips. The 

 fact that the hairs are never found empty is explained, either by the 

 extreme diti:usibility of small quantities of the scent, or by its replace- 

 ment by some of the white substance from the base. 



The object of these organs, of which only a rudiment is present in 



. * ' Kosmos,' iv. (1880) p. 387. t Sec this JourBal, ante, p. 780. 



