436 VARIATION AND ZOOGEOGRAPHY OF LIGUUS IN FLORIDA 



dark pattern of castaneozonatus . It appears however that in the case of tp 

 dineus at least, the new pattern occurs only in a complex hybrid colony comn ^ 

 of crenatus X roseatus X castaneozonatus; it may have the characters of eith 



s 



? 



Fig. 2. Young shells 

 tudineus. C. X 2. E 



fasciatus castaneozonatus, A; L. f 



shell 



s, 8' sutural 



and L. /. tet 



roseatus or crenatus in its embryonic and early neanic stag 



The inheritance 



factor for pattern may therefore be linked in some way with hybrid parentage, 

 rather than a pure de Vriesian mutation . 



In the case of marmoratus (PL XXXVII, figs. 9, 9a) on Key Vaca the new 

 pattern is apparently becoming of racial significance, although the race is still 



hybrid . 



No crenatus X roseatus hybrid is known, apart from the colonies also con- 

 taining castaneozonatus. 



IV. COLORS AND PATTERNS OF LIGUUS. 



The colors of IAguus fasciatus are in both the cuticle and the prismatic layer 

 of the shell. The cuticle is very thin and pellucid, except where colored green. 

 It is largely lost from the spire in adult shells. 



The green lines are wholly cuticular and may be readily scraped off with a 

 knife. They are often lost except immediately back of the lip in adult shells, 

 by abrasion or weathering and loss of the cuticle. Though the color is only 

 "skin deep" these lines are wonderfully persistent, being present in most indi- 



viduals of all varieties of L. fasciatus and crenatus. 



Even in melanistic varieties 



they may be traced as lines of blacker hue or different degree of reflection. By 

 acceleration they have extended back upon the last embryonic whorl, where 

 they are discernible as shallow grooves. The lines are usually marked in the cal- 

 careous layer below the cuticle by retarded deposition, indicated by sinuation o 

 the growth-lines, and a notch in the lip-edge at the termination of each green line. 

 The yellow pigment of xanthistic forms is below the cuticle. In the 8^™ *> 

 shell it is always strongest close to the outer lip, on the part of the shell as^ 

 formed. As growth proceeds, this color fades, so that it becomes fain er 

 farther it recedes from the end of the last whorl. In most xanthistic races, a ^ 

 or nearly adult individuals which have undergone a long resting stage have 



