162 INSECTS AFFECTING DOMESTIC ANIMALS. 
of the swallows, but it is evident that they are closely associated with 
this bird as a host. The figure will indicate the distinctive characters 
of the species, and comparison with the lectularia and inodora will 
reveal sufficient basis for considering it a distinct form. 
The species occurring upon the pigeon and the bat have not been 
recorded for America so far as I am aware, but it is quite probable that 
they may occur. They are evidently quite distinct species, and it would 
be a matter of interest to determine their occurrence here. 
Acanthia columbaria Jenyns is specially characterized by the rounded 
form of the abdomen, the slightly excavated prothorax, and the third 
joint of the antenne being longer than the fourth. 
Acanthia pipistrelli Jenyns has the abdomen narrowed, the prothorax 
moderately deeply excavated, the antenne intermediate, between lectu- 
laria and columbaria. 
a 
Fic. 92.—Antenne, showing comparative length of joints in a, Acanthia 
hirundinis; b, A. lectularia; c¢, A. inodora—enlarged (original). 
Considering the inaccessibility of the original descriptions to many 
students, it may be useful to repeat here the full technical descriptions 
as given by Jenyns (Annals of Natural History, 1839, Vol. III, pp. 
241-244): 
C. lectularius: Ferrugineo-ochraceus; thorace profunde emarginato, lateribus 
reflexis; abdomine suborbiculato, apice acuto; antennis articulo tertio quarto longi- 
ore. Long. 24 lin. Hab. In domibus. 
C. columbarius: Ferrugineo-ochraceus; thorace profunde emarginato, lateribus 
reflexis; abdomine orbiculato, apice subacuto; antennis articulo tertio quarto paulo 
longiore. Long. vix 24]lin. Hab. In columbis. 
C. hirundinis: Fusco-ferrugineus; thorace leviter emarginato, lateribus planis, 
abdomine ovato, apice subacuto; antennis brevibus, articulo tertio et quarto sub- 
aequalibus. Long. 1}lin. Hab. In nidis Hirundinis urbice. 
C. pipistrelli: Ferrugineo-ochraceus, nitidus; thorace profunde emarginato, lateri- 
bus paulo reflexis; abdomine ovato, postice attenuato; antennis articulo tertio 
guarto longiore. Long. 2lin. Hab. In Vespertilione pipistrello. 
C. columbarius: On comparing this species with the common house bug it will be 
found to be smaller and of a more circular form. The antennz are shorter and the 
joints are not quite so slender, and the difference in length between the third and 
fourth joints is not so considerable. The thorax is rather less hollowed out in front, 
the anterior angles less produced, and the sides less reflexed. The abdomen more 
nearly approaches the round, the lateral margins being very much curved and the 
greatest breadth exactly in the middle; whereas in the house bug the lateral margins 
are at first but little curved, and the greatest breadth rather behind the middle, 
The colors as well as the degree of the pubescence are similar in the two species. 
