384 Miscellaneous. 



" 8th. Difference of food is accompanied by one marked and per- 

 fectly constant colorational difference, and others which are not per- 

 fectly constant, in the larva, hut none whatever in the <3 5 imago : 

 Halesklota tessellaris, Sm. Abb., and H. Antiphola, Walsh. 



"9th. Difference of food is accompanied by several slight but con- 

 stant structural differences in the <S imago, but none whatever in the 

 5 imago : Clytus Robinice, Forst., and CI. pictus, Drury. 



" 10th. Difference of food is accompanied by a slight but constant 

 structural difference in both ^and $ imago : 1. Tingis Tilice, n. sp., 

 and T. amorphce, n. sp. ; 2 (doubtful). Diapheromera femoruta, 

 Say, and D. Velii, n. sp. 



" 1 1th (doubtful). Difference of food is accompanied by very strong 

 structural and colorational differences in the larva and in all proba- 

 bility by a constant structural difference of generic value in the 5 

 imago, the <S imagos being to all external appearances identical, and 

 the two insects belonging to different genera : Sphingicampa di- 

 stiyma S $ , Walsh, and Dryocampa bicolor <$ , Harris. 



" 12th. Difference of food is accompanied by marked and constant 

 differences, either colorational or structural, or both, in the larva, 

 pupa, and imago states: Halesidota tesellaris, Sm. Abb., and II. 

 Caryce, Harris, and hundreds of species belonging to the same genus, 

 and commonly considered as distinct species. 



" The constitution of the human mind is such, that the same evi- 

 dence carries with it very different degrees of weight when presented 

 to different intellects. Others will no doubt draw different conclusions 

 from the facts catalogued above ; but for my own part, as on the 

 most careful consideration I am unable to draw any definite line in 

 the above series, and to say with certainty that here end the Varieties 

 and here begin the Species, I am therefore irresistibly led to believe 

 that the former gradually strengthen and become developed into the 

 latter, and that the difference between them is merely one of mode 

 and degree." — Silliman's American Journal, September 1865. 



Note on the Cultivation of Eels. By M. L. Soubeiran. 



The author states that for several years past considerable quan- 

 tities of young eels have been taken at the mouths of the French 

 rivers and distributed in the inland waters ; but he adds that, from 

 his own experience, this course is not always judicious, and is fre- 

 quently unprofitable. lie mentions that in 185(5 certain landed 

 proprietors in the neighbourhood of Caen transported great quan- 

 tities of young eels to the ponds and other waters on their estates, 

 and after feeding them at great expense obtained nothing but loss from 

 their undertaking, the produce being only 150 francs against an ex- 

 penditure of 2220 francs. Besides this, the waters into which the 

 eels were introduced, and those into which they subsequently pe- 

 netrated, were entirely depopulated of other species of fish ; so that 

 the multiplication of eels must be regarded as in every respect 

 a losing speculation. — Comptes Rendus, 4th September, 1865, 

 p. 424. 



