256 
Rev. F. W. Hope on Insects 
lower, which is easily conceivable, because, further than as it may 
be essential for them to have a moderate power of vision above 
them to direct their course in their rapid flight, they cannot need 
so perfect a sight in that part of the eye, as the objects which 
more particularly require their notice, viz. their prey, food, &c. 
all occupy a situation level with or beneath their own, and thus 
are within the scope of the part of the eye most perfect in its 
sight, and comprehensive in its field of vision. 
I have thus roughly thrown together my few remarks and ideas 
on this matter, in the hopes of eliciting some further information 
on the subject. The varying relative proportions of the facets in 
the eyes of different insects, in some the difference of size being 
so conspicuous, as in the instances of Libellula vulgata and Scava 
selenitica before adduced, whilst in others it is but just perceptible, 
and in a great majority does not exist at all, is exceedingly cu- 
rious, and well deserves inquiry, which accurate observations on 
the living insects would most probably satisfy. 
DESCRIPTION OF THE FIGURES. 
Plate XXI. 
Fig. 2. Cornea of Libellula vulgata magnified, and showing about the relative 
proportions of the facets ; 2 a, longitudinal section or general outline of 
ditto from top to bottom of the eye ; 2 b, transverse section of ditto from 
anterior to posterior part. 
3. Cornea of Scceva selenitica magnified ; 3 a, longitudinal section of ditto ; 
3 b, transverse section of ditto. 
4. Front of the body of Asilus crabroniformis ; 4 a, cornea of ditto mag- 
nified ; s, the anterior edge of the eyes; p, the points of transition from 
the large to the minute facets. 
XLIX. On bisects and their Larvce occasionally found in 
the Human Body. By the Rev. F. W. Hope, F.R.S. 
and Pres. Ent. Soc. 
[Read 3d April, 1837.] 
In bringing this paper before the Society, one object is to set at 
rest a long disputed question as to whether true insects have been 
found in the human body. A second is, an anxious wish to 
render the science of Entomology practically useful. Instead of 
taking up the time of the members present with the conflicting 
