50 mtscelIjANEous papers. 



Ahdoviien broadly oval; segments 2 to 7, with an irregular row of 

 about twelve spines along posterior margin; spines on last two seg- 

 ments short but quite strong; color very dark brown to almost black. 



Redescrihed from numerous specimens including several cotypes 

 kindly furnished by Miss Daniel, 



J^ood plant: Grass. 



Hah'itat- Counties about San Francisco Bay, California. 



This species is described in Entomological News for November, 1904:, 

 page 29.5. I have taken specimens from grass on the campus of the 

 University of California, at Berkeley, Cal., where it was first found, 

 and from the same food plant in the Niles Canyon, Alameda County, 

 and on the campus of the Leland Stanford, Jr., University, Palo 

 Alto, Cal. It is easil}^ distinguished from the other species of the 

 genus in that the pterthorax is decidedly lighter colored than the rest 

 of the body, which is very dark brown to brown-black. 



(5) Sericothrips reticulatus, new species. (PI. 1, tigs. 9, 10.) 



MeasureinenU: Head, length 0.16 mm., width 0.20 mm. ; prothorax, 

 length O.IS mm., width 0.26 mm.; abdomen, width 0.48 mm.; total 

 body length 1.41 mm. Antennte: 1, 21yw; 2, 48//; 3, 54/<; 4, 54/<; 5, 51/^ 

 6, 69yu; T, 12/'; 8, 21/'; total, 0.336 mm. Colo7- brown, head and thorax 

 lightiar, and abdomen shading to dark brown at tip; legs yellow. Body 

 increasing in size gradually from head to sixth abdominal segment, 

 from where it tapers abruptly to the small ninth and conical tenth. 



Head small as compared with other segments of bod}"; cheeks arched, 

 edges roughened; frons with two prominent darkened angles directly 

 above basal segments of antennae and with an intermediate angular 

 depression. Head surface strongly reticulate, with no conspicuous 

 spines and with but few ver}- small hairs. Eijes large, prominent, 

 with coarse facets, not pilose, with light-colored outer borders, pig- 

 ment very dark purple. Ocell! absent. Mouth cone broad, pointed 

 bluntly at tip; maxillar}' palpi two-segmented. Antennm eight-seg- 

 mented, slightly more than twice as long as head, segments almost 

 uniform brown, sense hairs light colored and inconspicuous. 



Prothorax but slightly longer than head. It bears a few very small 

 hairs, but no spines. Mexothorax smallest segment of bod}^ excepting 

 the last two of the abdomen, with rnetathorax only a little larger, and 

 together they are wider, although not so large, as the prothorax. 

 They bear no conspicuous hairs or spines. Wo wings or wing-pads 

 are present. All legs are medium stout, unarmed, and with only a 

 few inconspicuous hairs; color yellow, tarsi tipped with brown. 



Abdomen, brown, shading darker toward the tip; broadly oval; seg- 

 ments 1 to 4 increasing in size gradually; segments 4, 5, and 6 about 

 equal, segment 7 tapering, 8 abruptly tapering to meet the very small 

 ninth and conical tenth. Entire upper surface of abdomen reticulate. 



