420 Mr. T. H. Briggs on 
antenne labelled “ Lonicere”!! I attach great import- 
ance to all the remaining points. Touching the larva, 
the usual description of ‘ yellowish” or “ greenish,” 
“with four rows of black spots,” is exactly equivalent to 
describing the imago as “ green, with red spots,” or a 
Smerinthus caterpillar as ‘green, with stripes on his 
side, and a horn on his tail.” I have found these spots 
on the larvee vary in the different forms or species in 
size and shape, although the following remark will apply 
to the caterpillars equally with the imagines, viz., that 
the general type only can be described—aberrant ea- 
amples will be found in which all the characteristics of 
some other type are fully developed, but such aberrancy 
seems confined to the then stage of the imsect’s existence ; 
for instance, that if im a number of Lonicere caterpillars 
we find one quite unlike the rest, and exactly resembling 
a Trifolii caterpillar, such caterpillar will not be a T'rifoli 
caterpillar accidentally in company with Lonicere, but 
will be a Loniceree caterpillar that from some unknown cause 
has assumed the markings of Trifolii, and the moth pro- 
duced from such caterpillar will be a typical Lonicere. 
Conversely, often when catching T’rifolii, say we imagine 
we have come across a solitary example of Lonicere. In 
most cases, such supposed Lonicere is only Trifolii imago 
having assumed the characteristics of Donicere, and, in 
all probability, produced from a typical Y'rifolii cater- 
pillar. I have several times personally met with examples 
of this singular fact, which, if further substantiated, will 
go far to explain what many authors have remarked, the 
occasional turning up of one species in the locality of 
another. In short, that mimicry is common throughout 
the genus. 
I now proceed to differentiate my two supposed species 
—comparing them with Pilipendule and Lonicere. 
(1.) Zygena Filipendule. 
Imago. Too well known for description. Antennz 
mediate in thickness between Lonicere and the two forms 
of Trifolii, those of the ¢ much thicker than those of 
the 9 ; a very narrow black border to hind-wings in 
both sexes. 
Larva. Full description set out in the appendix to 
this paper. 
