Scudder.] 
578 
[April 2, 
better known. There are, however, but four genera with nine species. 
In all, the antennae are brief and have the joints beyond the basal 
of more than usual equality. 
Although compared to the other Coreidse the subfamily Alydinae 
is to-day but poorly represented in America, whether in temperate 
or tropical regions, this was not the case in tertiary times ; for it 
was fairly well furnished with genera and species and as for num- 
bers in individuals no group of Heteroptera could compare with 
it. Most of the genera are extinct types and belong to the divi- 
sion of Micrelytraria in the immediate vicinity of Protenor and 
Darmistus, with slender and unarmed hind femora, but also as a 
general rule with distinctty and profusely though delicately spined 
hind tibiae. One genus, Rhepocoris, contains the bulk of all, and 
of the four or five species belonging to it, nearly all the specimens 
obtained belong to two closely allied forms, possibly to be regarded 
as only one. In Europe, but three fossil Alydinae have been rec- 
ognized, and these have all been referred to the division Alydaria. 
The family Pentatomidae has always held the first place among 
Heteroptera in tertiary deposits, but now its place must be dispu- 
ted by the Lygaeidae. This is due not only, though principally, to 
the exceptional abundance of Lygaeidae at Florissant, but also to 
the rather meagre proportion of the subfamily Pentatomida, as 
will appear below. In European deposits only a single species is 
known from amber, while fifty have, been exhumed from the rock 
deposits. They represent only four of the nine subfamilies, and 
the great majority belong to the two subfamilies Cydnida and Pen- 
tatomida, the former with sixteen species referred to four genera, 
the latter with twenty-five species referred to six genera. The other 
subfamilies represented are the Scutellerina with five species of two 
genera, both at Oeningen, and the Acanthosomina with four species 
of two genera, both at Radoboj. The American forms represent 
only the subfamilies Cj^dnida and Pentatomida, but in reverse pro- 
portion to what appears in Europe, the Cydnida being very well 
represented by twent} T -four species of six genera, nearly all of them 
by a number of individuals and one by a great many, the Penta- 
tomida on the contrary by only thirteen species of ten genera, and 
of each of these species more than a single example has rarely been 
found. While therefore the prevalent subfamilies are the same on 
the two continents, one has scarcely half as many representatives 
in America as in Europe, while the other has half as many more in 
America as in Europe. 
