4^^ AND ^"^^4 



JOURNAL OF VARIATION. 



Vol. IX. No. 7. July 1st, 1897. 



A New British Flea (Tryphlopsylla dasycnemus, sp. nov.). 



(Illustrated hj Plate). 

 By the Hon. N. C. ROTHSCHILD, F.Z.S., F.E.S. 



TriiphhipsijlJa dasi/cneuiufi, sp. nov. — De.scriptum — Front of the head 

 rounded, and more or less hairy, with four genal spines, situated as in 

 T. afisiinilis of British authors, and a small fifth spine at the anterior 

 edge of the antennal groove. The pro-thorax has sixteen spines. On 

 each side of the dorsal posterior edges of the first sLv segments of the 

 abdomen there is a siiu/le short spine. The ventral plates of the 

 ei(/htli segment display /n^fr hairs, of which the upper one is much the 

 longest. The uiiter surface of the tibia?, more especially of the hind 

 ones, is extremely hairy. 



Parasitic on Sore.v vuhjaris. 



The present species was discovered this year by Dr. Jordan, on the 

 above-mentioned animal. I am much indebted to him for specimens 

 and the beautiful drawings of the head, pro -thorax and tibia. 



The development of the wing, wing=scales and their pigments 

 in Butterflies and Moths. 



By J. W. TUTT, F.E.S. 



II. — The development of the pigment within the scales. — In 

 the previous part of this paper, we have seen that when the scale first 

 appears it is only a small protoplasmic cell, which very soon increases 

 in size, and flattens out, and finally assumes the outward shape of 

 the mature scale. A layer of chitin is then secreted over its entire 

 outer surface, so that the scale becomes a thin, flat chitinous bag, 

 filled with protoplasm, the chitin upon the upper surface of the scale 

 being striated, the lower surface smooth. Alany scales have two 

 sets of strife — a well-developed longitudinal set, and a finer transverse 

 set. These striations difiract the light, and give rise to the iridescent 

 colours observed on the wings of many lepidoptera. 



So long as the scales remain filled with protoplasm, they are quite 

 transparent, but the protoplasm afterwards becomes coarsely granular, 

 and appears to give place to a secretion from the h^emolymph, Avhich 

 contains the necessary material for the elaboration of the pigment, 

 the white coloration being different from the opaque whiteness notice- 

 able in air-filled scales. Mayer says that " the scales which are 



