:\IAYER : COLOR AND COLOR-PATTERNS. 185 



We see, then, that it is very common to find bands shrinking 

 away from either end, but very rare to find them broken in the 

 middle region. This, however, is only a special case of the law 

 enunciated by Bateson ('94), that the ends of a linera series are more 

 variable than the middle. Almost any row of spots also exhibits 

 the same law, in that the spots occup^nng the middle portions of 

 the row are similar one to another, Avhile those at the ends of the 

 series depart more or less from the type. (See Figs. 10-13, 

 Plate 2.) 



The position of spots which are situated near the edge of the 

 wing is large!}' controlled b}' the wing-folds or creases. In Meli- 

 naea egina (Fig. 96, Plate 8) there is a row^ of white spots near the 

 outer edges of the wings, and each of these spots is cut in two by a 

 narrow black line which extends along the wing-fold. Also in Cera- 

 tinia vallonia (Fig. 81, Plate 7) and in many other forms of the 

 Danaoid Heliconidae one often finds two creases in a cell, and in 

 this case there are two marginal spots, one on each crease. In 

 many other cases, however, the marginal spots are double in each 

 cell, although there is but a single w'ing-fold ; the spots in these 

 cases are situated at some distance on either side of the fold. (See 

 Figs. 95, 96, Plate 8.) Another very common condition is exem- 

 plified in Fig. 83, Plate 7, where there is a single marginal spot 

 situated upon the wing-fold in each cell. 



(3) Detdiled Discussion of the Laws of Color- Patterns. Figs. 

 6-14 and 16, Plate 2, are taken from special cases which serve 

 to illustrate the two chief laws of color-pattern, i. e., that spots tend 

 to be bilateral!}' symmetrical aliout an axis (HII, Figs. 6, 7) passing 

 througli tlie center of the cell parallel witli tlie nervures ; and 

 also, tliat spots of similar shape and color tend to be repeated in 

 a row of adjacent cells. 



In Fig. 7 the spots are separated in t!ie middle, l)ut still incline 

 outward symmetrically from tlie center; indeed, instances of dou!)!e 

 spots are very common. In such cases, how'ever, each half spot is a 

 reflection of its mate on the otlier side of the axis passing tlirougli 

 the center of the cell. 



Fig. 8 represents various eye-spots found in tlie Morphos, and 

 will serve to illustrate the law^s of ej'e-spots which have been enunci- 

 ated by Scudder ('89) and P>ateson ('94) . These spots occup}- the 

 center of the cells in which they are found. In cell II, for example, 

 is a large eye-spot with a crescent in its center, and it will be 



