3. ANTHRAX 527 



colour there but little concealed ; the disc also often has some inconspicuous 

 blackish tawny hairs intermixed and numerous closely adherent black scales, 

 so that these combined clothings give it a barer and darker appearance than 

 the rest of the thorax ; the tawny pubescence is richest in colour and most 

 dense on the fur-like collar, though that which extends from the collar down 

 the sides to the wing-base is nearly as much so, and then the pubescence from 

 the wing-base down the sides to and across the hindmargin is usually though 

 not always paler tawny ; on the postalar calli are from three to six long strong 

 yellow bristly hairs which are bent back towards the scutellum, and just above 

 the wing-base are about five similar but shorter more depressed and less con- 

 spicuous hairs ; near the front part of each absolute wing-base is usually a con- 

 spicuous snow-white patch of scales, but sometimes this patch has a slight 

 yellomsh tinge in certain lights, and occasionally is so much darkened as to 

 be rather inconspicuous, and moreover the patch becomes invisible if the 

 wings are somewhat raised because it is then hidden between the wing-base 

 and the thoracal pubescence ; pubescence on the flat slope on the hind part 

 of the disc rather coarse and not short. Pleurae with similar dense tawny 

 pubescence on all the upper part of the mesopleurae and metapleurae, but with 

 less dense and greyer pubescence on the lower part, while the absolute sternum 

 is dull greyish black and bears only slight pale pubescence. Scutellum 

 with pale tawny imbescence which is comparatively inconspicuous because 

 the abundant closely adhering black scales dominate the ground colour, but 

 with some long strong bristly hairs round the mai-gin which are often not 

 very easy to detect owing to their being merged in the dense surrounding 

 tawny pubescence, though about six of them round the tip are obviously 

 black ; a few thin inconspicuous yellow scales occur about the sides of 

 the margin. 



Abdomen oblong, being from the tip of the scutellum to the anus (when 

 denuded of pubescence) rather more than one and a half times longer than 

 broad ; in absolutely denuded specimens the sides of the two basal segments 

 are rufescent ; the whole of the four basal segments are densely covered with 

 tawny pubescence, which is richest in colour and longest down the sides 

 but is paler, less dense, and more irregular in length on the disc, while 

 black scales occupy a large portion of the disc of the fourth segment 

 and thereby reduce the tawny pubescence, and similar black scales 

 exist also on the disc of all the previous segments but are hidden by the 

 denser pale pubescence ; fifth and sixth segments with the marginal 

 l^ubescence deep black and quite as long and dense as the previous tawny 

 pubescence, but sometimes this deep black pubescence is a little broken 

 up by pale hairs, while on the disc the paler tawny pubescence still 

 extends but is usually weaker and consequently the middle ([uarter is 

 rendered more dull black through the dense adhering black scales ; seventh 

 segment with the marginal pubescence snow-white but with the middle 

 (apical) third again deep black ; the extreme basal corners of this seventh 

 segment have some inconspicuous black hairs, but the black coloring both at 

 these basal corners and at the tip is mainly composed of more raised longer 

 black or brownish black scales among which however towards the margin are 

 some longer black hairs ; the dorsal surface of the abdomen bears no 

 trace of pale scales. Belly dull black, with conspicuous but not at all 

 dense unarranged pale yellow pubescence of about the same length as that on 

 the dorsal side ; on the extreme inner margin of the dense marginal 

 pubescence (which appears paler when viewed from beneath than from above) 

 are several elongate black scales and a few long black hairs which are 

 almost concealed by the long dense pale tawny pubescence ; disc of the 

 belly densely clothed with close black scales and with rather slight bands 

 of pale yellow scales on the hindmargins of the second to fifth segments 

 (inclusive), and these yellow scales are rather numerous and more extended 

 on the fourth segment but yet are scarce in comparison with the black scales 

 and do not occur on the middle of the segment ; some irregular scales occur 

 on the sixth segment ; a few tawny hairs occur between the black and the 

 white tufts at the end of the sixth segment. Genitalia very small, orange. 



Legs all dull black ; hind pair slightly thickened, especially on the tibiae. 

 Pubescence on the front coxae abundant and pale yellow on the front part but 



