82 NATURAL SCIENCE. 



Feb. 



have at last put on Pace to break the Record, and we trust that their 

 effort will meet with the success it deserves, especially as it cannot 

 possibly injure the finances of this ponderously respectable publication. 

 The fatuity of the present enforced alliance of diverse groups is obvious 

 to any dipper into the volume ; for the diversity of treatment meted out 

 by the recorders to their respective groups is no less than that of the 

 groups themselves. 



In this connection we may state that, as at present understood, 

 the Central Zoological Bureau, projected by Dr. Field and others, 

 intends to issue its slips and its Record in parts, according to the 

 various subjects. This alone would be enough to give it an advantage 

 over the present Zoological Record. In reply to many enquiries, we 

 take this opportunity of stating that Dr. Field may be addressed at 

 No. 67, Rue de Buffon, Paris, but that, during February, he will be 

 in England, intent on advancing his project. 



'Warning Colours. 

 Professor Felix Plateau, who is so well-known by his work 

 upon the sense of sight in insects, has lately published an interesting 

 paper upon the " Magpie moth." This insect has often been quoted as 

 an example of " Warning colour " in all three stages of its existence. 

 The white, yellow, and black of the caterpillar are repeated in the 

 moth, while the pupa is brown, banded with yellow. Professor 

 Plateau carried out his studies in so thorough a fashion that he not 

 only caused other animals to eat the caterpillars, but ate them 

 himself, " after some natural hesitation." The flavour, instead of 

 being disagreeable, proved to be the reverse, reminding him a little of 

 almonds. No less than 43 per cent, of the caterpillars are devoured by 

 ichneumon flies, while spiders, beetles, a few birds, and, according to 

 the experiments of Mr. Beddard, quoted by Professor Plateau, certain 

 monkeys and other animals will eat them with pleasure. It is difficult 

 therefore to see exactly where the advantage of the warning colour 

 comes in. So small a percentage could be saved by this means. 

 Professor Plateau's conclusions are very much the same as those 

 arrived at by Mr. Beddard in an article upon the " Magpie cater- 

 pillar " in the Gentleman s Magazine for 1890, but they are based upon 

 a larger series of experiments. It would be as well if all the examples 

 of warning coloration were subjected to asc areful an examination. 

 Professor Plateau's paper is to be found in the most recently issued 

 part of the Memoires de la Soctete Zoologique de France. 



Mimicry. 



Professor Plateau, however, is not entirely against current 

 theories of the kind. But he appears to think, and rightly, that they have 

 been a little too much used as an universal explanation. In a paper 

 in Le Naturaliste figures are given of the " Merveil du Jour " and of 



