632 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 51 



The fonn of the body varies much; in some species, as Scymnus 

 coniferarum, it is elongate fusiform with prothorax obovate, more 

 than twice as long as broad, and, with the ninth segment conical, 

 twice as long as broad, mucH narrower than the eighth segment; in 

 other species, as Scymnus cervicalis, the form is rather broad with 

 the segments of about the same size and only sUghtly tapering pos- 

 teriorly, the prothorax is trapezoidal, anteriorly broadest, laterally 

 rounded, about twice as broad as long, and the ninth segment is 

 semicircular, about twice as broad as long, and not much narrower 

 than the eighth segment; still in other species, as Ceplialoscymnus ( ?), 

 the general shape is the same as in Scymnus cervicalis, but all seg- 

 ments have laterally pecuhar large prolongations. The outline of meso- 

 thorax and metathorax of the group is that typical for the majority 

 of the CoccineUid larvae; it is trapezoidal, broadest in front, and 

 differs from the transversal-oval dorsal outline, characteristic of the 

 foregoing groups and stiU characteristic of the abdominal segments 

 of the present and the subsequent group. This trapezoidal form is 

 mainly due to the following development of the mesothoracic and 

 metathoracic pleural areas (fig. 13, pi. 120) . As mentioned previously 

 (page 629), the mesothoracic and metathoracic spiracles move down 

 into the protopleurite; and this area fuses more or less closely with 

 the adjacent part of the tergum and also with the deuteropleurite 

 into a sub triangular region, thus givmg the impression as if the an- 

 terior portion of the spiracle bearmg tergal area had been enlarged 

 and dropped downward to the stemopleural suture. There it 

 touches and is more or less confluent with the upper edge of the 

 elongate, triangular, swollen, presternal area (prst, fig. 3, pi. 118) which 

 points downward to and normally touches the unpaired ventral 

 notch. The spiracle-bearing extension does not carry any setiferous 

 tubercle or spme. By the development of this anterior pleurite the 

 rest of pleurum is forced backward, and fused into the swollen, sub- 

 triangular region, which extends upward from the stemopleural 

 suture m its entire length to the teimmus of the tergopleural suture. 

 On the thoracic segments a pair of longitudinal chitinizations occur on 

 the terga, and, on the abdominal segments a small setae-bearing tuber- 

 cle is developed on the scutal area, on the sphacular area just below 

 the small parascutal area, on the pleural lobe, and on some of the ster- 

 nal areas. In Cephaloscymnus ( ?) , deviating in many ways, the pleural 

 lobe is extraordinarily developed into a broad horizontally flattened, 

 setae-bearmg process (fig. 24, pi. 121); similar structures have been 

 described m other Scymnini. The hypopharyngeal bridge is strong; 

 the mandible has a molar-hke base and the apex of the mandible is 

 single in aU the genera and species represented in the United States 

 National Museum, except Cryptolaemus montrouzieri, in which form 

 the apex is divided into two teeth; in the hterature, however, several 



