884 SUMMAKY OF CURRENT RESEARCHES RELATING TO 



in 26 cases ; while, on tlie contrary, they selected the plain as one of 

 the first three in only 25 cases, and one of the last four in 75 cases. 

 On the whole, then, it seems clear that bees are affected by colour, 

 and that their favourite colour is blue." 



M. Paul Bert has made some interesting experiments on the 

 small fresh-water crustacean belonging to the genus Daphnia, from 

 which he concludes that they perceive all the colours known to us, 

 being, however, specially sensitive to the yellow and green, and that 

 their limits of vision are the same as ours ; but Sir John, as the 

 result of his own experiments with Daphnia under different parts of 

 the spectrum, considers that the limits of vision of Daphnia do not, at 

 the violet end of the spectrum, coincide with ours, but that, like the 

 ant, it is affected by the ultra-violet rays. 



a. Insecta. • 



Beetle with Proboscis like that of Lepidoptera* — H. Miiller is 

 moved to return to this subject,']' by the opinion which Dr. H. A. 

 Hagen, of America, has expressed, of the improbability of the truth of 

 his conclusions. He admits the purely theoretical character, in the 

 present state of our knowledge, of the hypothesis which derives the 

 Lepidoptera from the Trichoptera, but his object in appealing to 

 the sudden transition to the Lepidopteran type of mouth in the case of 

 the beetle was intended, not to prove a similar suddenness of transi- 

 tion from the Phryganeid mouth, but the possibility of a less pro- 

 longed series of intermediate stages between this mouth and that of 

 the Lepidoptera than would otherwise appear to be probable. 



The lengthened mouth-parts of some Phryganeidaa only serves, he 

 says, to aid his theory. From the fact that the twenty-six American 

 species of the beetle in question (Nemognatha) have prolonged maxillae, 

 while in the six Old-World species, these are of the normal Coleop- 

 teran structure, he deduces in support of his theory: (1) that the 

 New World are derived from the Old World forms in this case, and 

 hence (2) from common ancestors; (3) that consequently the time 

 which the proboscis took to develope was only that which intervened 

 between the emigration of a member of the genus to the New World 

 and the evolution of the first species belonging to the modified type. 

 Hence the time of transmutation is even shorter than at first appeared 

 probable. The interesting beetle which gave rise to the discussion is 

 well figured here. 



Structure and Hatching of Egg-capsules, &c., in Mantis.J — 

 The capsules consist essentially of a series of stories, placed one above 

 the other ; in the centre of each story, C. Brogniart exj)lains, is a 

 chamber which is divided by a vertical partition into two and contains 

 the eggs ; it communicates with the exterior by a tube, leading to the 

 front, whose lips form imbricated scales ; the spaces surrounding this 

 chamber are empty. The eggs are so arranged that the heads of the 



* Kosmos, viii. (1881) pp. 57-61 (4 figs.). 



t See this Journal, iii. (1881) p. 239. 



X Comptes Reudus, xciii. (1881) pp. 94-6. 



