GARMAN : THE REPTILES OF EASTER ISLAND. 13 



side, and two have 4 on one side and 5 on the other ; six have normal prefrontals, 

 that is, the prefrontals are in contact between frontal and internasal, two have 

 an azygous prefrontal with the regular prefrontals in contact, and two have the 

 azygous separating the prefrontals. Of nine Hawaiian individuals seven have 

 28 rows of scales each, two have 30 ; five have 4 labials on each side, two have 

 4 on one side and 5 on the other, one has 3 on one side and 4 on the other, and 

 one has 3 on each side ; eight have normal prefrontals and one has an azygous 

 shield separating the prefrontals. The Easter Island specimens show an increase 

 in the number of scales on the head ; those from the Hawaiian Islands a slight 

 decrease. In the labials alone the four on each side in front of the suborbital, as 

 seen in the greater number of the Cryptoblephari, are represented by an average of 

 four and two-thirds in the Easter Island specimens noted above, and on the 

 Hawaiians by an average of little more than three and nine-tenths. If such averages 

 may not be accepted as differences sufficiently tangible for the establishment of 

 the variety, paschalis, they may at least be said to indicate the process of forming 

 new species by means of hereditary tendencies in variation. There is nothing to 

 separate the two localities in the coloration ; the redness of the end of the tail is 

 apparent on some. Among the specimens collected by Dr. H. B. Bigelow are 

 some very dark ones, slaty on the belly, on which the light lines are almost 

 invisible ; these are marked " taken under rocks," a locality which probably 

 accounts for the difference in color, the species undergoing considerable changes 

 on removal from light to darkness or the reverse. There is nothing in the struc- 

 ture to distinguish the dark ones from the light ones as represented in Fig. 7. 



