220 SPHAERODACTYLUS. 
certain anguids, without which respiration would be impossible owing to the 
integumentary armament. _ 
Since this memoir was prepared for publication some time ago it behooves 
me to comment supplementally on Noble’s valuable paper The bony structure 
and phyletic relations of Sphaerodactylus and allied lacertilian genera, with the 
description of a new genus published in the American museum novitates, 10, 
March, 1921, no. 4, p. 1-16, 8 figs. 
In this paper Noble gives the results of his studies of the skeletal features 
of a number of gekkoid genera made with the aid of cleared preparations. With 
one of his conclusion I most heartily agree, namely that the Eublepharidae 
constitute an unnatural assemblage and it is evident that the family serves no 
useful purpose, being simply an omnium gatherum combining the end results of 
several lines of descent not closely related. Thus the family ‘‘instead of being 
a very ancient group as hitherto believed,. ..may be a very recent assemblage, 
even if a conservative one.” 
Noble derives Sphaerodactylus from a genetic series of which Gonatodes, 
Lathrogecko, and Lepidoblepharis represent successive stages of modification. 
Various internal characters are cited and illustrated to support the evidence 
derived from a comparative study of the digital apices; this is presented very 
persuasively and while it may be correct it is by no means certain that too much 
stress is not placed upon fortuitous similarity. I believe that often skeletal 
modifications are very easily brought about by changes in feeding habits or 
through very many other causes and often even what are apparently such 
ephemeral features as colour-characters may be very conservative. In other 
words the external facies of an organism may offer, within reasonable limits, 
better criteria for postulating relationships than certain skeletal features. 
Noble’s work on the claw-sheaths is very valuable, and while here again it 
is possible that similarity may not indicate actual phyletic relationship neverthe- 
less the probability is very considerable that some such descent has taken place 
when this evidence is taken in connection with the internal characters of hyoids 
and girdles. 
It would be very interesting to know Mr. Noble’s views on the connection of 
Aristelliger with this series for it is almost inconceivable that this relationship 
is not close. I strongly suspected this genus to be the closest ally of the 
sphaerodactyls. That no fossils remain to cast light upon the subject is not 
surprising in view of the fragility of their bony skeleton. 
The sphaerodactyls are preéminently island gekkos and they probably occur 
