ACHATINELLA VIRIDANS. 127 



In Nuuanu valley the shells vary from typical green color 

 to a form in which the dark green is replaced by blackish- 

 chestnut, light green by yellow (pi. 25, fig. 4). A specimen 

 of the rather widely-spread form of Upper Nuuanu, pale 

 yellow with light yellowish olive streaks 1 , is figured on pi. 31, 

 fig. 6a, coll. by Mr. Richard A. Cooke. A small, thin-shelled 

 form was found only on a few isolated bushes at the head of 

 the valley just west of the pali. It is chestnut-brown with 

 lighter streaks and pale lines below suture -and periphery; 

 lip-callus narrow; length 15.8, diam. 8 mm. PI. 31, fig. 6, 

 coll. by R. A. Cooke. 



In Manoa Gulick collected the typical green form (pi. 25, 

 figs. 1, la) ; others having black, others olive (pi. 25, fig. 3) 

 or chestnut streaks on a yellow ground. There is now no 

 forest low in Manoa valley. 



Palolo has the same range of forms shown in figs. 1 to 3. 

 A black-streaked shell is figured (pi. 25, fig. 2, collected by 

 Gulick). Really typical viridans does not go eastward of 

 Palolo, so far as I know. It is a rather homogeneous race, 

 having the same pattern but in varying shades and colors. 

 Probably green, olive, chestnut and black are varying stages 

 of oxidation of the same pigment ; or perhaps the dull ground 

 of some specimens may be due to cleaning with hot water. 

 In Palolo the forms rutila and subvirens also occur, whether 

 associated with the typical viridans pattern I do not know. 



Doctor Newcomb has given the following description of the 

 soft parts. A. viridans: " Animal light gray; tentacles and 

 tentacular sheath dark slate; mantle thick, yellowish-brown. 

 Tentacles strongly clubbed, short and robust, when extended, 

 longer than the shell. ' ' 



A. rutila: " Animal small in proportion to the shell, of a 

 uniform yellowish-white, retractile part of upper tentacles of 

 a light-brown; tentacles filiform and slightly clubbed; foot 

 very broad, long as the shell ; mantle same color as the ani- 

 mal." 



Eastward of Pialolo the typical viridans pattern disappears, 

 and the color-forms rutila and subvirens replace it. These are 

 often hybridized with more or less blending, so that the ap- 



