NOCTUINA. 185 



the species is avoided. The terms normal first and second 

 lines have already been constantly used in this work and will 

 be at once recognised as lines which really seem to have 

 some connection with the structure of the wings, so constantly 

 do they appear, one before, the other beyond, the middle of 

 the fore wings. Nearer the base is usually — or frequently — a 

 more or less incomplete line, which in other groups becomes 

 the outside margin of a basal blotch, and which is known 

 as the basal line ; nearer the hind margin than the second 

 line is the subterminal line, usually a mere pale division of 

 the clouded apical and hind marginal colouring, but which 

 often assumes sharp and very definite form. Between the 

 first and second lines, and placed in the discal cell, are usually 

 two spots large enough to extend completely across the cell 

 and divide it into sections. That nearer the first line is 

 usually somewhat round, and is known as the Orbicular 

 stigma ; the other, nearer to the second line, is generally 

 larger and somewhat broadly kidney-shaped, and is known 

 as the Reniform stigma. Below the Orbicular stigma, on the 

 other side of the median nervure, and commonly placed with 

 its base touching the first line, is a third spot, very frequently 

 present though not so reliable as the other two, and of a 

 wedge-shape, known as the Claviform stigma. If the reader 

 will look back to the genus Sesia, he will find in nearly every 

 species a bar or blotch at the apex of the discal cell ana- 

 logous to the Reniform stigma, as indeed is the central spot 

 in so many other species ; and in Euthemonia russula and 

 Dasychira pudibunda he will find it more decidedly indi- 

 cated. In some exotic Bonibycina allied to Euthemonia — ■ 

 notably some South African species — both the Reniform and 

 Orbicular stigmata are strongly marked. To go even further 

 back, the markings in the discal cell of the butterflies of the 

 genera Argynnis and Melitcea are of a somewhat analogous 

 character, and a resemblance can readily be traced. It is 

 desirable that these four lines and three stigmata, with their 

 names, should be fixed upon the mind, or the descriptions of 



