Mytilaspis. 8i 



MYTILASPIS COCCULI, sp. nov. 

 (Plate XXI.) 



Female puparium {fig. 4) lon<; and narrow, widening very gradually towards 

 the posterior extremity; dark purplish -brown, opaque, with a very narrow 

 irregular paler flattened border ; dorsal scale transversely marked by curved 

 lines of growth, the more prominent of which are of a paler colour. Pellicles 

 very pale yellow, transparent, occupying (in the most mature scales) less than 

 one-third the total length — -in one instance, less than a quarter; the second 

 pellicle has the abdominal segments without lateral points. Ventral scale 

 greenish, well developed, undivided {fii;. 5), of rather solid structure, with a 

 small aperture near the anterior extremity, and a large ragged orifice at the 

 hinder end from which the young larvae make their escape ; the surface of the 

 ventral scale is minutely but deeply pitted. It would, however, be dangerous 

 to give specific value to this character, as it is probably dependent upon the 

 surface of the leaf. Length 3 to 4 mm. Greatest breadth 075 mm. 



Male puparium {figs. 2 and 3) similar to that of female, but smaller ; lines 

 of growth not so pronounced, a pale transverse band marking the position of 

 the usual hinge near the posterior extremity. Ventral scale greenish, well 

 developed and rather solid, with a broad median longitudinal division. Length 

 7'5o mm. 



Adult female {fig. 9) whitish, abdominal extremity reddish-fulvous; cephalic 

 extremity narrowest ; abdominal segments widest, with prominent lateral lobes. 

 There is a distinct transverse fold across the anterior part of the head on the 

 level of the rudimentary antennas; this feature is constant in all specimens 

 examined. The abdominal segments are much wrinkled and seem to be more 

 highly chitinised than the anterior parts, appearing of a darker colour in 

 prepared specimens. The two last abdominal segments each bear four or five 

 stout spines on the lateral margin, and there is sometimes one on the preceding 

 segment also. Parastigmatic glands not readily discernible, but a small group 

 of three or four can sometimes be seen on the border of the anterior stigmatic 

 opening. Pygidium {fig. 10) with evenly rounded extremity. Squames and 

 lobes as in Myt. citricola, the lobes rather smaller and less prominent; there 

 are occasionally three instead of two squames caudad of the second marginal 

 notch. The marginal pores are large and conspicuous, as are also the cylin- 

 drical spinnerets in connexion with them. The dorsal tubular spinnerets are 

 either absent or very inconspicuous. Circumgenital glands in five groups : the 

 median with from one to six orifices, upper laterals with eight to thirteen, and 

 lower laterals with six to eight. Length averaging i mm. 



Adult male {fig. 6) of normal form. Colour creamy white ; head, median 

 joints of antennce, and sides of thorax tinged with pale purple ; dorsal plates of 

 mesothorax outlined with reddish ; apodema reddish. Antennas hairy, nearly 



M 



