Pomona College Journal of Entomology 525 



of articles: I, 0.09 mm.; II, 0.07 mm.; Ill, 0.5 mm.; IV, 0.2 mm.; V, 0.19 mm.; 

 VI, 0.48 mm. (spur O.SS mm.), total 1.53 mm. Rostrum — Reaching jnst beyond 

 first coxa?, dusky. Proihorax — Dark except basal margins wliicli are lighter. 

 Meso- and Metathorax — Each with four small black spots on dorsum. Abdomen — 

 WitJi transverse dark markings and dark s|)ots on the dorsum, segmentation 

 obscure dorsally and distinct ventrally, genital plate dusky. Cornicles — (Figure 169 

 E). Cylindrical, slightly wider at base, short, black, length 0.17 mm. Legs — - 

 Normal, dusky, cox!P color of body; femurs darker at apices; tibiae dark at bases 

 and tips; tarsi dark. Style — (Figure 169 G). Triangular or conical in shape, 

 dark; length 0.17 mm., width at base 0.13 mm. 



Hosts — Occurs in great numbers upon Cabbage and Cauliflower (Brassica 

 oleracea L.), Wild Mustard {B. campestris L.), Black Mustard (B. nigra Koch.), 

 Wild Radish (Raphanus sativus L.). 



Locality — Throughout the entire state. Date of collection — Nov. 2, 1910. 

 Serial number 8. 



This insect often does considerable damage to cabbage, cauliflower and other 

 cruciferous plants in the garden. It collects in great colonies and may completely 

 cover the host. It is partially controlled by natural enemies, the predaceous ones 

 being Hippodamia convergens Guer., Coccinella californica, Hippodainia maculata 

 DeG., and the larvae of the Syrphid flies. The internal parasite, Diaeretus calif or- 

 nicus Baker, does good work in the southern part of the state. 



It may be controlled artificially by spraying with Kerosene Emulsion, Whale- 

 oil soap. Tobacco decoction, or Carbolic Acid Emulsion. 



Aphis ceanothi-hirsuti n. sp. 

 WINGED VIVIPAROUS FEMALE (Figure 170 A) 



Length of body 1.4S mm., width of mesothorax 0.6 mm., wing expansion 

 6.8 mm. 



Prevailing color — Very dark brown to almost black. Head — As wide as 

 prothorax, black. Eyes — Very dark red. Antennae — (Figure X70 a). Dusky 

 throughout, reaching nearly to base of cornicles, very sparsely haired, lengths of 

 articles: I, 0.06 mm.; II, 0.06 mm.; Ill, 0.38 mm.; IV, 0.22 mm.; V, 0.2 mm.; VI, 

 0.44 mm. (spur 0.3 mm.) ; a large number (19-23) circular sensoria on III. Rostrum 

 — Reaches just to metathorax, light yellow, brown at base and dusky at tip. Pro- 

 thorax — Black, with distinct lateral tubercles. Mesothorax — Black with well 

 developed muscular lobes. Metathorax — Dusky, but not as dark as mesothorax. 

 Ventral surface of thorax very dark brown or black. Abdomen — Dark amber 

 brown, with marginal and transverse dark markings, all black behind a transverse 

 line drawn across abdomen in front of the cornicles one-quarter the distance from 

 the base of the cornicles to the base of the abdomen. This seems to be character- 

 istic. Ventral surface dusky or dark brown. Cornicles — (Figure 170 b). Cylindrical, 

 straight, black; length 0.3 mm. Legs — Normal, coxae black, femora of prothoracic 

 legs amber with tips only dusky ; femora of meso- and metathoracic legs amber at 

 base and remainder dusky ; tibae of all legs dark at extreme base and the tips ; tarsi 

 dark. Wings — Hyaline. Primary — I^ength 3.2 mm., width 1.1 mm.; costal vein 



