248 
[October 
dish brown, surmounting 3—4 cells; membranules rather small, whitish; angle 
of hind wings very acute. Antecubitals 13 ; postcubitals 10—12; two discoidal 
areolets commencing with 2, in one hind wing with 3. 
Length 45.^ mill. Exp. % 55 mill. Abd. 33 mill. Front wing % 27 mill. 
Hind wing 25^ mill. Hind femur % mill. Pterost. infer. % 2J mill. 
One S ; 9 nnknown. There are four distinct colors in this insect, 
viz.: black, lilac, green and yellow, whence the specific name. The 
contrast between the green, which is almost bluish-green, and the 
bright vivid yellow is very striking, and the details were most of them 
noted from the living insect. The contrast is just as apparent in the 
dried specimen. In vastus % 9 there is a somewhat similar contrast, 
which I did not notice in my description, the meso- and metathoracic 
Bcutels being yellow more or less bright and the thoracic notum green¬ 
ish yellow j and in one specimen there is a bright yellow spot on the 
greenish-yellow dorsal vitta of the 2nd abdominal. This elegant little 
species can be confounded with no allied U. S. species but adelphus 
Selys, owing to its minute size; and it differs from adelphus Is^, in the 
face being immaculate. 27ic^, In the occiput not being “blackish” be¬ 
hind. 3rcZ, In the back of the head not being blackish immaculate. 
4^/i, In having no black spot behind the coxae of the hind legs. 5^A, 
In the sides of abdominal joints 8 and 9 not being black, immaculate. 
The superior abdominal appendages of adelphus are described as 
having their tooth spring from the outside edge of their inferior sur¬ 
face and point downwards^ whereas in quadricolor it springs from the 
inside edge and points obliquely inwards at an angle of 45°. Ith^ Al¬ 
though quadricolor is larger than adelphus^ its posterior femur is ^ 
shorter. The femora of adelphus are immaculate, except a yellow 
point at the knee; those of quadricolor are immaculate except that 
the anterior femora and trochanters are posteriorly yellow.—Of the 
foreign allied species it is separated at once from vulgatissimus, simiU 
limus^ pulchellus^ graslini and Jiavipes^ all 5 of Europe, and from me- 
laenops (Japan), and Lucasii (Africa), by its face being immaculate. 
From a closely allied species (length 48 mill.) inhabiting thfe Kurile 
Islands, south of Kamtschatka, of which only a single specimen in 
bad condition is known to exist, G. kurilis, it difiers as follows; Isi, 
Kurilis has the occiput “ almost straight,” and what is singular “ not 
ciliated.” 'Ind^ The dorsal abdominal vitta of kurilis is continuous on 
joints 4—7, in quadricolor it is widely interrupted at the tip in joints 
