72 ENTOMOLOGICAL SOCIETY 
and has often a median longitudinal carina. The metepisterna 
and metepimera are large and distinctly separated. 
The wings. Curious and constant differences may be seen in 
the shape of the fore wings by which the family is readily divided 
into two groups. With the Microcentri the wings expand with 
approximate equality on both cephalic and caudal borders towards 
the distal border which is abruptly rounded. With the Macro- 
centri, on the contrary, the caudal margin has almost invariably 
an angle, more or less distinctly marked, from which a long curve 
sweeps up to the apex which is near the cephalic margin. The 
submarginal vein extends out into the wing a short distance be- 
hind the costa and more or less gradually joins the costa at some 
distance from the base. From the point where it joins the costa 
it becomes the marginal. It is often broken near the marginal, 
and this makes a good division ofiheAficrocentri'mto two groups. 
The marginal is almost invariably longer with the Microcentri 
than with the Macrocentri. With the latter it is- sometimes en- 
tirely lacking, in which case the stigmal proceeds directly from 
the submarginal (Aphycus) . The postmarginal varies greatly 
in length. It may be wanting {Entedori) or may extend 
nearly to the tip of the wing ( Gastrancistrus] . The stigmal, 
with its club and hook, is always more strongly marked with the 
Macrocentri than with the Microcentri. With the latter the 
uncus is often represented by a chain of large cells. The spu- 
rious veins are usually only seen in certain lights and are unimpor- 
tant. The Jirst spurious connects the second with the submargi- 
nal. The second spurious extends from the submarginal to a 
point below the tip of the wing. The third spurious is usually 
given off from the second, but sometimes from the first, and 
reaches the margin at a point cephalad of the second. The 
tegulcz vary from triangular to quadrilateral in shape, and vary 
also in size and color. The wings are in general evenly covered 
by a minute pilosity except at base. In certain genera (Aph- 
elinus} an oblique hairless streak, of varying width, extends from 
below the stigma to near the base of the fore wing. In certain 
Encyrtids also there is a hairless streak near the tip of the wings. 
In Trichogramma the pilosity is arranged in regular lines. The 
borders of the fore .and hind wings are furnished with cilia (ex- 
cept along costa) . In Psilophrys the marginal cilia are not de- 
