170 DE- A. D. IMMS ON 



less massive than those of the female. They are armed with two very small apical teeth 

 placed side hy side, and there are no other definite teeth. Below the apex of each 

 mandible the inner margin is produced for less than half its length into a sharp cutting- 

 edge. The inner angle of each mandible is somewhat produced, and to it is attached 

 the tendon of the adductor muscle {add.). 



The ginghjmus {ging.) is directed obliquely outwards and lies above and partly behind 

 the condyle (cond.). To the outer angle of each mandible is attached the tendon of the 

 abductor muscle (abd.), but there is no special process developed. 



The first maxillie each consist of a five-jointed palp, a membranous galea, and a stout 

 lacinia, carried by the cardo and stipes (PI. 38. fig. 11). The joints of the palpi are 

 related to one another in length in the proportion of 17 : 9 : 15 : 18 : 22, — the second 

 joint being much the shortest and the apical joint the longest. The galea {gal.) is 

 membranous and unarmed. The lacinia {lac.) is strongly chitinised and armed with a 

 pair of small apical teeth situated side by side ; along the inner margin of the lacinia is 

 a row of stiff elongate setae. The cardo {car.) and stipes {st.) present no special features ; 

 the former is the larger of the two joints. 



The second maxilla? {labium) consist of a quadrangular submentum {m 2 in PI. 38. fig. 9), 

 a well-developed mentum {m x ). They differ considerably in form from those figured by 

 Grassi and Sandias (1897, pi. 19. tig. 7) for Haploembia solieri (Ranibur). 



Arising from near the base of the submentum are the labial palpi {l.p-), which are 

 three-jointed. The joints are related to one another in length in the proportion of 

 approximately 12 : 14 : 17. In some specimens, however, the two basal joints are 

 practically equal in size. A vestigeal palpiger is present, and its limits are indicated by 

 an indistinct suture (pgr.). Distally, the mentum carries a pair of large external lobes 

 or paraglossa {g.), which are the counter-parts of the galeae of the 1st maxillae. Situated 

 on either side of the median line, and between the paraglossae, are a pair of small pointed 

 lobes representing a divided ligula {I.) and corresponding to the lacinia of the 

 1st maxillae. The mentum exhibits indications of a paired formation being divided into 

 halves by an indistinct median line which is much less chitinised than the rest of the 

 sclerite. The hypopharynx appears as a median jirojection from the floor of the mouth. 

 Viewed from above it appears quadrangular in form, and longer than broad. Its dorsal 

 surface is invested with a covering of extremely minute scales, which are pectinate along 

 the distal margin. In many instances the middle tooth of each scale is prolonged into a 

 slender spine. On the ventral surface of the hypopharynx the scales become less 

 numerous and disappear. Such scales have also been noted and figured by Enderlein 

 (1909, p. 16S, fig. 3) in Oligotoma saundersi, Westvv., who regards them as taste-scales. 



The Thorax. — The prothorax is narrower than the head, sub-quadrate, but slightly 

 broader than long. Its anterior margin is straight and the sides slightly diverge 

 posteriorly. The hind margin is produced into a median convexity (PI. 37. fig. 1). 

 The anterior fourth of the tergum is definitely constricted off from the rest by means of 

 a deep transverse sulcus. At right angles to the latter and terminating in it anteriorly, 

 is a shallow median longitudinal groove. Both the anterior margin and the sides are 



