24 NORTH AMEETCAN THYSANOPTERA. 



Food plants: Oranges, wild vetch, burr clover; foliage of beets, radishes, 

 pea vines, and lettuce; pear blossoms and foliage. 



Note.— This insect is a serious pest on oranges, alfalfa, pear trees, and 

 various garden crops. 



(21) Heliothrips fasciapennis Hinds, Mon. Thys. N. Amer., Proc. U. S. Nat. Mus., 



vol. 26, p. 171, figs., 1902. 

 Habitat: Amherst, Mass. 

 Food plants: Grasses. 



9. Genus ECHINOTHBIPS new genus. 



(Described on page 37.) 



(22) Echinothrips mexicanus new species. (For description see p. 37.) 



Habitat: Acapulco, Mexico. 



Specimens taken from a small potted plant on shipboard in San Fran- 

 ciscOj Cal. 



10. Genus DICTOTHRIPS Uzel. 



(23) Dictothrips reticulatus Crawford, Pomona College, Journ. Ent., vol. 2, no. 1, 



p. 155, figs., 1910. 



Habitat: Guadalajara, Mexico. 



"Taken on blossoms of native acacia-like tree" (Crawford). 



11. Genus SERICOTHIIIPS HaUday, 1836. 



(24) Sericothrips variabilis Beach, 1895. Redescribed by Hinds, Mon. Thys. 



N. Amer., Proc. U. S. Nat. Mus., vol. 26, p. 143, figs., 1902. 



Habitat: Iowa; Massachusetts; Yosemite Valley and San Jose, Cal. 



Food plants: Cucumber, grass, smartweed; in blossoms of buckthorn and 

 mountain lilac (Ceanothussp.?) in Yosemite Valley in California at an altitude 

 of 5,000 ft. The California specimens should probably rank as a distinct 

 new variety of this species. 



(25) Sericothrips pulcheUus Hood, Bvil. 111. State Lab. Nat. Hist., vol. 8, art. 2, 



p. 363, 1908. 



Habitat: Muncie, 111. 



Food plants: Hop-tree (Ptelea tri/oliata). 



Note." — Mr. Hood notes that "this species is very close to Sericothrips 

 variabilis Beach, but the coloration is distinctive. In living specimens 

 examined under a hand lens, the head and prothorax are velvety black and 

 without luster, due no doubt to the microscopic reticulation." 



(26) Sericothrips cingulatus Hinds, Mon. Thys. N. Amer., Proc, U. S. Nat. Mus., 



vol. 26, p. 141, figs., 1902. 



Habitat: Amherst, Mass.; Nebraska City, Nebr. 



Food 2)lants: Various grasses. The writer has collected specimens of this 

 insect from grass at Nebraska City, Nebr., which have fully developed wings. 

 These are broader and clear white in the basal fourth and slender and uniform 

 gray-brown in the outer three-fourths. 



(27) Sericothrips apteris Daniel, Ent. News, vol. 15, p. 295, November, 1904. 



Redescribed by Moulton, Tech. Ser. 12, Pt. Ill, Bur. Ent., U. S. Dept. Agr., 

 p. 49, 1907. 



Habitat: Counties about San Francisco Bay, California. 



Food plants: Various grasses and weeds. 



Note. — Many specimens of this thrips collected recently indicate a close 

 relationship to S. stanfordii Moulton. Some specimens are almost xmiformly 

 brown. 



