444 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 10 



siderable outlay in money for its eradication which is now possible 

 because of its limited distribution. 

 {Berkeley, Cal, Jan. 1, 1916.) 



Bibliography and Synonymy 



Flor, Bui. See. Imp. Nat. Moscou, XXXIV, pp. 380, 386, 393, 398-400, 1861. 

 LcEW. F., Wien, Ent. Zeit., XXXII, p. 230, 1882. 



Ver. Zool. Bot. Ges. Wien, XXXVI, p. 160, 1886. 



Ver. Zool. Bot. Ges. Wien, XXXVII, p. 22, 1887. 

 Ferrari, Ann. Mus. Civ. Genoa (2), VI, 1888. 

 PuTON, Catalogue Caen, 1889. 



Kessler, Ber. Ver. Kassel, XXXIX, pp. 19-25, 1892-1893. 

 Massalongo, Mem. Acad. Agric. Verona (3), LXIX, pp. 39-42, 1893. 

 Tavares, Annses Naturses, VII, 1900. 



Trotter and Cecconi, Cecidotheca Italica fasc. Ill, No. 69, 1901. 

 Rtjbsaamen, Marcellia, Padova, I, Xo. 11, pp. 62-63, 1902. 

 Trotter, Nuovo Giorn. Bot. Ital., Fierenze (2) XX, No. 55, pp. 28-29, 1903. 

 Tavares, Broteria, Lisboa, IV, pp. 33, 223, 1905. 

 Makchal et Chateau, Mem. Soc. Hist. Nat., XVIII, p. 268, 1905. 

 DiCKEL, Zeit. Wiss. Ins. Biol., I, p. 402, 1905. 

 OsHANiN, Verz. palaarkt. Hemip., II, p. 372, 1907. 



Grevillius & NissEX, Arbeit. Rhein-Bauern-Verein fasc. Ill, No. 68, 1908. 

 HouAED, Zoocecidies des Plantes d'Europe, pp. 437, 438, 1908. 

 Crawford, Mthly. Bui. Cal. Hort. Com., I, No. 3, pp. 86-87, 1912. 

 SuLC, Sitz. Kon. Boh. Ges. Wiss. Prag, pt. XVI, pp. 49-52, 1912 (1 plate). 

 OsHANiN, Katal. palaarkt. Hemip., p. 129, 1912. 

 Crawford, Bui. 85, U. S. Nat. Mus., pp. 94-95, 1915 (2 figures). 

 EssiG, Inj. & Ben. Ins. Cal. 2nd. edit., pp. 68-70, 1915 (2 illustrations). 

 Thomas,! Gartenflora, XC, pts. 2 & 3. 

 BoHLiN,' Ent. Tidskr., XXII, pp. 81-92 (1 figure). 

 HiERONTMUS,! Pax, Herbarium Cecidologicum fasc. VIII, No. 231.' 



Trioza lauri Targioni-Tozetti, Resocont. Soc. Ent. Ital., p. 19, 1879. 



As the dates could not be secured for these references, they are placed at the end. 



Explanation of Plate 20 



Fig. 1. — The tomato psyllid, Paratrioza cockerelli Sulc. Nymphs and their white 

 peUet-like excrement on the underside of a tobacco leaf. Enlarged two and one half 

 times. (Original. IPhoto by Dept. of Scientific Illustration, Cal. Agrcl. Exp. Sta.). 



Fig. 3. — The laurel psylHd, Trioza alacris Flor. Leaf-gaUs on young shoot of laurel 

 tree caused by the nymphs. The white cottony masses are the old skins of the 

 nymphs. Natural size. (Author's illustration, Inj. Ben. Ins. Cal. 2nd. ed., 1914). 



Fig. 4. — The laurel psyUid, Trioza alarcris Flor. Adults, nymphs and the cast skins 

 of the latter on a leaf of the laurel tree. Enlarged 6 times. (Author's illustration, 

 Inj. Ben. Ins. Cal. 2nd. ed., 1914). 



