GURUENT NOTES. 91 



the faintest impression, but otherwise act as do our own. The fact 

 that tliey are possessed only liy hirva3 wliich are exposed more or less 

 fully to the light, while those larva? which are endophytous, or other- 

 wise hidden from light, generally lack them, is in itself proof that they 

 perform the ordinary functions of sight, however low in degree. In 

 the imago state the great majority of insects have their simple eyes in 

 addition to tlie compound eyes. In many cases, however, the former 

 are more or less covered with vestiture, which is another evidence that 

 their functions are of a low order, and lends weight to the view that 

 they are useful chiefly for near vision and in dark places. The com- 

 pound eyes are prominent and adjustable in proportion as they are of 

 service to the species, as witness those of the common house-fly and 

 of the Libellulidse, or dragon-flies. It is obvious from the structure of 

 these compound eyes that impressions thi-ough them must be very 

 different from those received through our own, and, in point of fact, 

 the late experimental researches of llickson. Plateau, Tocke and 

 Lemmermann, Pankrath, Exner, and Viallanes, practically establislied 

 the fact that while insects are short-sighted and perceive stationary 

 objects imperfectly, yet their compound eyes are better fitted than the 

 vertebrate eye for apprehending objects set in relief or in motion, and 

 are likewise keenly sensitive to colour. So far as experiments have 

 gone they show that insects have a keen colour sense, though here 

 again their sensations of colour are different from those produced upon 

 us. Thus, as Lubbock has shown, ants are very sensitive to the ultra- 

 violet rays of the spectrum which we cannot perceive, though he was 

 led to conclude that to the ant the general as^ject of nature is 

 presented in a way very different from that in which it appears to 

 us. In reference to bees, the experiments of the same author prove 

 clearly that they have this sense of colour highly developed, as, indeed, 

 miglit be expected when we consider the part they have played in the 

 development of flowers. While these experiments seem to show that 

 blue is the bee's favourite colour, this does not accord with Albert 

 Miiller's experience in nature, nor with the general experience of 

 apiarians, who, if asked, would very generallj^ agree that bees show a 

 preference for white flowers." 



Dr. F. Werner has compared (Biolog. CentralhL, xiv., pp. 116-9) the 

 relative length of the intestine in vegetarian and insectivorous 

 Orthoptera. The result was unexpected. The plant-eating Acridiidae 

 have a short almost straight gut, rarely larger than the body ; whilst the 

 Locustidae have a larger gut, usually spirally coiled, especially in 

 Barbitistes and rhaneroptera. Werner believes that the length and 

 coiling of the intestine have nothing to do with the diet, but are corre- 

 lated with the shape of the body and the habits of life. — Journal 

 Royal Microscopical Society. 



W^ 



KOTES ON COLLECTING, Etc. 



Short notes fhom tue excuange baskets. — Dr. Gunning (Mont- 

 rose) writes on Dec. 7th : — " Sugaring was an utter failure here from the 

 last week in July until the middle of November, when Orrhodia vaccinii 

 and Scopelosoma satcUitia appeared in fair numbers, and continued to 

 do so until quite the end of the month. Last year Calocampa vetmta, 



