December, '09] JOURNAL OF ECONOMIC ENTOMOLOGY 439 



marginal and spiracular spines, anal plates and spines — the similarity 

 is evident. 



The Hemispherical Scale 



Saissetia Jiemisphcerica (Targ.) 



Plate 19, Fig. 16; Plate 20, Fig. 4 



Lecanium hemisphwriciim Targ., Studii sul. Coco., pp. 26, 27, etc. (1867). 



Chermes anthurii Bdv., Ent. Hort, p. 328 (1867). 



Chennes fiUciim Bdv., Ent. Hort, p. 335 (1867). 



Chermes hihernaculoritm Bdv., Ent. Hort, p. 337 (1867). 



Lecanium coffece Sign., Ann. See. Ent. Fr., 5, III, p. 435 (1873). 



Lecanium deaumontice Dougl., Ent. Mon. Mag., XXIV, p. 95 (1887). 



Lecanium clypeatnm Dougl., Ent Mon. Mag., XXV, p. 58 (1888). 



Lecanium hemisphwricum var. liihernaculorum Ckll., Bui. Bot. Dep. Jamaica, 

 p. 71 (1894). 



Lecanium hemisphwricum var. filicum Green, Ent. Mon. Mag., XXXIII, pp. 

 70, 77 (1897). 



Lecanium (Saissetia) coffece var. clypeatum Ckll. & Parr., The Industrialist, 

 p. 164 (1899). 



Saissetia Jiemisphwrica Ckll., The Ent. Student, II, p. 32 (1901). 



Coccus coffece Kirkaldy, Fauna Haw., Ill, pt 2, p. 105 (1902). 



The cqjnmon name of this scale is descriptive of its form, although 

 it is not exactly hemispherical but a little elongate and frequently 

 higher than broad. The shape, smooth surface, brown color, and the 

 minute pale dots of the skin which are easily seen with the aid of a 

 hand-lens, will distinguish this common species. As in all species of 

 this genus, the derm is filled with microscopic pores. 



A number of species and varieties have been described by early 

 authors which are now known to be synonyms. A form known as 

 filicum, occurring on ferns has been held to be a different species, but 

 a long study of this form and its transference from various hosts to 

 ferns and vice versa indicates that not even varietal rank should be 

 considered. 



Mr. W. C. Thro, in Bui. 209, Cornell Univ. Agr. Exp. Sta., de- 

 scribes filicum as varying from hemisphcerica in the number of "fringe 

 spines" on the anal plates, but a careful examination of Mr. Thro's 

 slides reveals the ordinary number of spines, although small, in his 

 specimens which were immature. 



This species is perhaps more widely (if possible) distributed 

 throughout the world than 8. olece, and infests a wider range of plant 

 life. It occurs only in greenhouses in temperate regions. 



