338 ORTHOPTERA OF NOVA SCOTIA. PIERS. 



Acad. Xat. Sc, Phila, 67, pp. 293-322), in which after care- 

 fully studjdng 1,540 spedmens from North and South 

 America, they finally unite all native Amsrican forms of 

 Gryllus under on3 spe^iac nams, Gryllus assimilis (Fabricius, 

 1775), the type-locality of which spe2ie3 is Jamaica, and with 

 a range extending from Canada to Patagonia. Simple 

 as this solution of the Gorgon knot may appear, it is doubtful 

 if it will meet with immediate approval, at least from 

 many field orthopterists who are familiar with the habits 

 as well as other points of difference of the various forms in 

 moderately large areas. Their contrary arguments must 

 be heard before a decision is reached. In the meantime 

 until this matter becomes clearer, we will endeavour to fit 

 in with the hitherto prevailing nomenclature. Further 

 remarks on the nomenclature of our Xova Scotian form will 

 be given on page 348. 



Considering the very great difficulty of clearly defining 

 between various so-called species, forms, or variants, which- 

 ever they may be, the best we can do regarding analytical 

 keys is to give that of Dr. E. M. Walker (1904), founded on 

 metric distinctions, for the determination of Ontario forms, 

 which agrees very closely with the keys of Scudder (1902)^ 

 Blatchley (1903), and AValden (1911), and which is as good 

 as any that are available along such lines. We must bear 

 in mind, however, that the valu€ of metric diagnostic charac- 

 ters is very much doubted by some recent specialists. Lutz 

 in his paper before referred t^o, shows the liability to error 

 in using lengths of wing-cover, wing and ovipositor as char- 

 acters of specific importance in the genus Gryllus; and Rehn 

 and Hebard (1915) believe that the mass of evidence on these 

 features in Lutz's paper is absolutely convincing. With 

 this caution, we may say that this key should at least embrace 

 such forms as may occur here, subject to the variation which 

 is met with from region to region. Should subsequent 

 writers sustain Rehn and Hebard's contention that there 



