based on the principle of Cephalization.—Insects. 27 
Parallelism between Pteroprosthenics and Pterometasthenics. 
roup. ‘They are 
the mouth mandibulate, although unlike in that the latter 
(or highest species) are also suctorial; alike also in being with 
few exceptions terrestrial, and also in being permaturative. 
Hemipters an ipters, or the two second subdivisions, are 
alike in having the mouth suctorial, and feeble species for their 
size as compared with those of the first subdivisions. 
The typical Orthopters and the Aphantpters, or the types under 
the two third subdivisions, consist alike of saltatorial and podo- 
metasthenic species. 
(2.) Between the three subdivisions of the Pterometasthenics and 
the three of the Pteroprosthenics.—The more prominent of the rela- 
tions between Coleopters and Apipens have just been mentioned. 
ose of Hemipters and Amplipens are still closer; Hemipters 
ing so near to Homopters in structure, and especially in the 
composition of the rostrate mouth, that they have been placed 
together in the same tribe by most entomologists. 
The Orthopters and Neuropters, or the third subdivisions of 
each, show a degree of approximation in the close resemblance 
in form between the Neuropterous Mantispids and the Orthop- 
terous Mantids, indicating a tendency to run off into the same 
style of amplificate structure, and also in the Cricket-like form of 
the Neuropterous Borei; more profoundly in the resemblance in 
structure of mouth and the nature of the metamorphosis between 
the Neuropterous Perle and the Orthopterous Phasmids, as re- 
marked upon by Westwood. ‘ : 
us the grand divisions of the Pterometasthenics constitute 
4 parallel series to those of the Pteroprosthenics. 
he further parallelisms, under both the Pteroprosthenics and 
Pterometasthenics, between the third of the grand divisions of 
each and the first and second have been explained on pages 20 
to 22, and 24. 
_ The affinities and analogies of species and groups appear hence 
to be fully exhibited in the system of classification presented, 
far more so than in any arrangement of osculant circles. 
(8.) Between the several groups as to the number of subdivisions, 
“and the grades of types constituting them.—The number of subdi- 
‘Visions in the groups, both the higher and lower, is three, as In 
most of the classes and orders that came under consideration in 
Article I, 
