54 
THE SUBSTITUTE. 
wliich the limbs which iheynt first 
)){)ssesscd are gradually reduced in 
size, and ultimately entirely lost, 
till the animal retains only the 
appearance of a short sluitgish 
vermiform animal, in which not 
only are the wings and legs, but 
also the antennte and the organs 
of the mouth, almost entirely ob- 
literated, and even the articulated 
condition of the body nearly lost. 
Such is the apparently helpless 
condition of the females of a 
rather extensive group of moths, 
which have been long well known 
to German entomologists under 
the name of Sacktiiigers, of which 
the smaller species constitute the 
genus Psyche, whilst some of the 
larger were formed by the late 
llev. I.ansdowne Guilding into 
the genus Oihetievs. The memoir 
on the two West Indian species 
observed by that author is con- 
tained in the fifteenth volume of 
the ‘ Linnean Transactions,’ and 
is one of the most valuable contri- 
butions to the Science contained in 
the volumes published by that 
Society. Whilst the plates, how- 
ever, which illustrate this memoir 
clearly prove the close affinity of 
the two insects, the males are very 
distinct in form from each other, 
and oughtevidently to be regarded 
as types ol separate subgenera. Of 
their intimate connection with the 
smaller European species, known 
under the generic name of Psyche, 
(but which have lately been distri- 
buted by M. Bruand, in an 
excellent monograph on the group, 
into various subgenera,) there can 
be no possible doubt; indeed, the 
largest British species cannot he 
separated generally from Oiketi- 
cus. Of Oikelicus niyricaits males 
only were at first captured in this 
country, which were illustrated by 
Mr. Curtis in his ‘British Ento- 
mology,’ under the name of Pen- 
thophora viyricans. Its generical 
relation with Penthophora i.s, how- 
ever, entirely unfounded, whilst 
even its family connexion there- 
with is at least questionable.” 
Mr. Westwnod then, after no- 
ticing the habits of the larva and 
male imago, proceeds to describe 
the female perfect insect as fol- 
lows ; 
“The body has all the soft ap- 
pearance of that of the larva of a 
wasp or hee, and is of a pale dirty 
whitish colour, except the upper 
side of the head and thoracic seg- 
ments, which are brown; the first, 
fourth, fifth, sixth, seventh, eighth, 
ninth, tenth and eleventh seg- 
ments of the body are furnished 
at the sides with a pair of spira- 
cles, from which the trachea" may' 
be seen to radiate through the 
thin skin of the body. On the 
under side of the body is a row of 
nine small brown spots in the 
middle of the segments, com- 
mencing on the segment next to 
the head, those on the thoracic 
segments being close together be- 
tween the minute rudiments of 
legs. The head has three deep 
circular impressions in front form- 
ing a triangle ; the eyes appear to 
be merely irregular black spots, 
with the surface continuous and 
destitute of facets ; the an- 
tenna) are rudimental, consi.sting 
of a minute exarticulated pair of 
appendages on the under side of 
the front of the head. Between 
the rudimental antennas there is a 
transverse impression in the place 
of the month, which is alternately 
puffed out and withdrawn, but no 
opening is visible. The legs aro 
