292 NEW YORK STATE MUSEUM 



Other aim or power than the perpetuation of the species. This, in brief, 

 is the story of the female scale. It is different with the opposite sex. 

 The scale, usually of a different form, is secreted by the young (pi. 2, 

 fig. 6), and the same process goes on till the second molt, and then rudi- 

 ments of limbs, antennae and wings are developed, and later appears the 

 minute two- winged creature fpl. 3, fig. 12), which forsakes its sheltering 

 scale and looks for a mate. This tiny insect lost its appendages while 

 living under the protecting scale, and in time developed others much 

 more delicate and refined. 



Other scale insects are not protected by a shield of excreted matter and 

 cast skins as are those mentioned above. They vary much in general 

 appearance and habits. Some live in galls, others, like Kermes, re- 

 semble and are frequently taken for galls, while still others may be found 

 in ants nests. The soft, brown Lecaniums are among the most 

 common unarmored scale insects, and they can usually be distinguished 

 by their oval, somewhat hemispheric bodies. The more typical Coccidae 

 are represented by the "mealy bug," Dactylopius longispinus 

 Targ., and the elm bark louse, Gossyparia ulmi Geoff. The former 

 is common in greenhouses and the latter is found in considerable numbers 

 on elms in many cities and villages. Neither of these lose their appendages 

 with the first molt, as do the armored scales, and they retain the power 

 of locomotion to a certain extent, at least. Coccidae belonging to this 

 group are usually covered with a whitish, protective excretion, which is, 

 for example, cotton-like in Gossyparia and granular in the " mealy 

 bug." 



Number of species. The number of described species of scale in- 

 sects is very large. A check list of the Coccidae of the world ^, pub- 

 lished by Prof. T. D. A. Cockerell in 1896, lists over 800 species, and a 

 supplement^ to this adds over 300, making a total of about 11 00. Some 

 of these will doubtless prove to be varieties, but new species are con- 

 stantly being added to the hst. A most interesting study of the forms 

 occurring in the state of Massachusetts has been prosecuted by George 

 B. King, of Lawrence (Mass.), who has succeeded, by collecting and 

 compiling, in bringing together a list of no, aside from several unidenti- 

 fied, species of scale insects known to occur in that commonwealth. 

 Compilation of earlier records and the aid generously given by other 

 entomologists have made it possible to prepare a list of 78 species' of 

 scale insects known to occur in New York state {see p. 354). Many 

 additions will doubtless be made to this list by farther collecting. 



1 Illinois state laboratory ot natnral history. Bui. 1896, v. 4, art. 9. 

 2 " 1899, V. 5, art. 7. 



