THE ORDER OF SNAKES— OP^ZZ)/^. 



xs 



Nothing now remains but to give a few hints with regard to the 

 names adopted by naturalists for the scales of the head and body in 

 Ophidian reptiles ; and for this purpose three woodcuts are added, to shew — 

 1st. The head from above, with nine scales, whereof 



r is the rostral shield v vertical 



f anterior frontals (2) s superciliary (one over each eye) 



/posterior frontals (2) o occipital (2) 



2nd. A side view of the head of a (non-venomous) snake : — 



Shewing — n' and n the nasals. 



/. The loreal (absent in nearly all Australian venomous snakes). 



a. Anterior ocular. 



p. Posterior ocular (generally two behind each eye). 



f. Temporals. Many venomous snakes have a large temporal shield wedged in 

 between the two last upper labials, in such a manner as to give it the appearance 

 of a labial shield. 



M. Tipper labials — There are generally six of these shields in venomous snakes (we 

 may say always six, never more). Non- venomous serpents have seven or more. 



* The lower labial shields, which correspond to those of the upper jaw, and are 

 reduced to six in poisonous serpents. The labial shields have not been con- 

 sidered of much value in distinguishing one group from the otlier ; but, after 

 examination of many thousand specimens, it may be safely asserted that, by 

 these shields alone can the harmless or venomous character of snakes be ascer- 

 tained. This rule does not apply to Sea Snakes, nor to the Blind Snakes of the 

 family TyphlopiJoe, but to Australian venomous and innocuous colubrine snakesonly. 



