Miscellaneous. 273 



which exceeds the maxillae in length. On the dorsal plates of the 

 thorax and ahdomen the clothing is as follows : — The posterior hairs, 

 which are much longer, are distributed in regular rows, and the 

 anterior hairs, which are of smaller size, are scattered without any 

 particular order. A similar distribution is to be observed upon the 

 ventral plates of the ninth segment. On the other ventral plates 

 the little hairs show no particular arrangement, and the ventral 

 plates of the second segment are quite without hairs. The superior 

 extremities of the pleurae of the nieso- and metathorax, as also the 

 wing-like scales, are clothed with hairs, arranged upon the pleurae 

 in two, upon the scales in three rows. Further, the unpigmented 

 cuticle of the abdomen is covered with transversely arranged rows 

 of the smallest possible hairs. The coxae of the first pair of legs are 

 covered with hairs only in front, as also the coxae of the other legs. 

 The trochanter, the femur, the tibiae, and the tarsus have their 

 whole surface covered with little hairs. Much larger hairs are to 

 be noticed at the anterior lower angle of the coxae and trochanter 

 in each leg. The femora have at their hinder angles two curved setae. 

 In the distribution of the spines upon the tibiae and tarsi no devia- 

 tions are to be remarked. — Zoologischer Ameiger, February 9, 1885. 

 p. 75. 



Completion of the History of Chaitophorus aceris, Fabricius. 



By M. J. LlCHTENSTEIN. 



In the ' Comptes llendus' of the 17th June, 1867, MM. Balbiani 

 and Siguoret gave the history of the brown Aphis of the maple. 

 These observers traced only half the biological evolution of the in- 

 sect ; M. llitzema of Leyden, and Mr. Buckton in England, have 

 added some details to those furnished by the French naturalists ; 

 and I can now give the complete series of the curious metamor- 

 phoses of this animal. 



The ova of Chaitophorus aceris, concealed during the winter 

 beneath the buds or in the fissures of the bark of the maple (here 

 Acer monspessulanum, Linn.), are hatched in the early days of 

 March ; they furnish an apterous false female or pseudogi/ne, which, 

 without concourse with the male sex, and after four moults at six 

 days' intervals, or in from twenty to twenty-five days, brings forth 

 some young Aphides, a portion of which acquire wings, and which 

 spread for longer or shorter distances, according to their powers of 

 locomotion, over the maples of the neighbourhood. This second 

 phase, to which I have given the name of the emigrant pseudo- 

 yi/ne, is agamic like that which preceded it, undergoes, like it, four 

 changes of skin, and produces not only two, but three different forms 

 of Aphides — one like itself, the second furnished with long hairs, and 

 the third adorned with leaflets around its periphery. 



All this has been told by MM. Balbiani and Signoret, at least in 

 part, for it is especially to these latter forms that they paid atten- 

 tion. They say that they could not trace them further, and inquire 



