4 IOWA STUDIES IN NATURAL HISTORY 
and all will either supplement or aid in the verification of the 
distributional data of the species concerned. 
Keys for the identification of the species are not given, for 
it is probable that additional forms should be included in the 
fauna of the islands, and a key without embracing all the species 
would scarcely be justifiable. However, not much difficulty should 
be encountered in the determination of the forms discussed here, 
for in the case of the more obscure ones the brief diagnosis ap- 
pended should be sufficient for ready delimitation. 
The collection of pentatomids consists of approximately eight 
hundred pinned specimens, of which about one-fifth are Edessa 
meditabunda. In addition, many duplicates of the seven common- 
est species were taken. In all, seventeen species are represented 
in the lot. Nine of the seventeen were taken on Barbados and 
all the forms found on that island were also discovered at An- 
tigua. Seventeen species are here recorded for the latter island. 
Of the nine species taken at Barbados seven occur in the 
United States north of Mexico. The other two are exclusively 
Neotropical. Of the seventeen Antigua species fourteen occur 
also in the United States and three are strictly Neotropical. 
By way of indicating something of the relative abundance, 
the following table showing the number of specimens taken of 
the eight least common forms, irrespective of the island upon 
which they were found, is appended. 
Podisus fuscescens 1 specimen 
Podisus sagitta 3 specimens 
Sphyrocoris obliquus 3 - 
Arvelius albopunctatus 13 ni 
Berecynthus delirator 15 seg 
Thyanta casta 19 je 
Thyanta antiguensis 24 “5 
Vulsirea violacea var. nigrorubra 64 2 
Each of the remaining nine forms is represented by a greater 
number of specimens than the last above mentioned. 
It will be seen that the collection comprises a great number 
of borderline species, that is, forms which are commonly found 
between temperate and equatorial America. As a whole, the 
