PABACOROTOCA AKERMANl (waRREN). 359 



abdominal ridges, the peculiar al-doiniiial tergites of different sliapes. 

 and the dorsal position of the spiracles. The niinil)ering of the segments 

 follows the scheme given l:>y Berlese.' The bilobed nature of the 

 prothoracic swelling (pr. sw.) is shown. 



Fig. 4. — x 75. Front view of head, showing setose labrum. ventral, 

 membranous portion of clypeus (clij.). discharge pore (d.) of mandilmlar 

 gland, antennal pits, and the two concavities of occiput (oc.) in which 

 the bilobed prothoracic swelling is lodged. 



Fig. 5. — x 75. Side view of head, showing huge palpiger (2>0>.) and 

 2-jointed maxillary palp (j)-)- 



Fig. 6. — x 75. End-on view of head, showing cheeks (gn.) and 

 mouth-parts. 



Fig. 7. — x 75. Back (ventral) view of head, showing mouth-parts 

 in situ. Labial palp (/. j).) is one-jointed. 



Fig. 8. — x 75. Isolated tergite of 2nd abdominal segment. X-shaped 

 sclerite with the two limbs on each side connected by a curved plate of 

 chitin ; one pair of limbs clasps the abdominal stalk and the other 

 supports the angle of the upturned portion of the abdomen. The latter 

 are perforated by the 2nd pair of abdominal spiracles. 



Fig. 9. — x 375. Longitudinal vertical section of body through one 

 of the typical abdominal sternites, showing its subdivisions {pst. ms. s. 

 and mt. s.) and relationship to the general cuticle (cu.) of the l:>ody. 

 It is clear that the sclerites are to be regarded merely as areas of 

 concentrated chitin within the general cuticle. 



Fig. lU. — X 90. Left view of partially extruded sexual apparatus of 

 the male. The internal sac {i. s.) issuing from the chitinous penis (ch.p.) 

 or middle lobe is the distal end of the ejaculatory duct. Lateral lobes 

 are obliquely placed, the right one (/•. I. I.) being ventral and the left 

 (l. I. I.) dorsal. Two horseshoe-shaped chitinous pieces at the base of 

 the lobes may be perhaps regarded as representing tergite X. 



Fig. 11. — X 70. Right view of extended male apparatus. Segment X 

 bears two lateral setose plates apparently representing the 10th sternite. 



Fig. 12. — x 70. Left view of extended male apparatus, showing the 

 so-called " basal piece " {b.}}-) of Sharp and Muir. 



Fig. 13. — x 70. Dorsal view of extended male apparatus. 



Fig. 14. — x 70. End-on view of extremity of female abdomen, 

 showing the divided lOth sternite above and the median 10th tergite 

 below. 



Fig. 15. — x 90. End-on view of extremity of female abdomen. 

 1 Berlese, Antonio, ' Gli Insetti,' p. 266. Milan, 1909. 



