13 SCUTATINA. 



jointed), inserted on a tubercle below the margin of the head, and 

 which is rarely visible from above ; first, fourth, and fifth joints more 

 or less distinctly petiolated. Ocelli 2, seldom wanting. 'Prono- 

 tum large, quadrangular or hexagonal.* In the memhrane of the 

 elytra mostly more than five nerves. Tarsi 2 — 3-jointed ; between 

 the two claws on the last joint two membranous lobes or pulvilli. 



Abdomen. — lu both sexes the six abdominal segments are always visible, 

 and none of them take the form of genital segments. On the under 

 side the posterior margin of eacli segment is more or less concave, the 

 sixth being still more cut out, roundly or somewhat squarely, for the re- 

 ception of the genital segments. Genital segments. — In the 5^ , as a rule, 

 only the third segment is visible; it is usually convex, channeled, and 

 rounded posteriorly; or it has only a slight depression ; or there is a wide 

 opening, with strong processes. In the $ , on the upper side, the third 

 segment is visible, more rarely the posterior margin of the second. On 

 the under side the first segment appears as two triangular plates, with their 

 inner margins shut close together ; the second segment appears as two 

 small, triangular plates, whose inner angles are distant from each other ; 

 the third segment as two triangular or irregularly oblong plates, which lie 

 behind the first plate and go up between the first and second, either touching 

 each other on their inner angles or sides or lying wide apart ; the other 

 plates sometimes visible in the centre belong to the anal or genital organs. 



Family 1.— CYDNIDtE. 



Head small, short, rounded. Nostrum reaching to the middle 

 coxae, rostral channel short. Antennce short or moderate. Eyes 

 small, not prominent. Pronotum quadrangular, transverse. Scit- 

 tellum triangular, long, the apex depressed. Prosternum with a 

 rostral channel. Ifesosfernum with a slight keel. Leys strong; 

 tibics with strong spines in rows ; tarsi trimerous. 



Abdomen.- — Genital segments .- in the $ the plates of the first are not 

 ridged at their junction in the centre, and the parallel inner margins of the 

 triangular plates of the third segment do not meet. Gen. 1, Sehirus. 



* These and other terms indicative of form are only approximative, none of 

 the figures being mathematically regular. In the hexagonal form of pronotum 

 the part adjoining the head is the anterior margin ; joined to this are the diver- 

 gent sides; from the lower end of these proceed the convergent hinder sides, the 

 sixth side being formed by the posterior margin. 



