244 Prof. J. C. Schiódte on the Morphology 
nished, the spout-groove, which sometimes occurs as a con- 
tinuation of the spout, and, finally, the evaporating-surface, 
which surrounds the opening and is intended to retain the 
secretion while it evaporates, and to prevent it from running 
own over the neighbouring parts, particularly the second 
pair of spiracles, To this end the surface is very finely gra- 
nulated, and at the same time undulated-rugose. In the 
detail of their structure these parts exhibit so many varieties, 
that they are often of importance for the systematic diagnosis 
of the animals; and as they have hitherto been very little 
noticed, a general account of their distribution and principal 
forms will be of use. I shall principally take the examples 
from among the Danish species, which are quite numerous 
enough (more than three hundred species are known from 
Denmark). 
In the family of Cmices there are some in which there 
seems to be no external indication of a glandular apparatus ; 
amongst the Danish genera, Phimodera and Odontoscelis are 
in this case. In the others the opening is always situated on 
the side, at a greater or smaller distance from the coxe, but 
exhibiting many varieties as to size, shape, spout-groove, and 
evaporating-surface. In Tetyra hottentotta and maura the 
opening is at a distance both from the coxe and from the 
anterior edge of the metathorax ; it is very narrow, and has a 
long straight groove, with narrow and sharply raised edges, and 
terminating with a sharply defined rounded outline; the evapo- 
rating-surface extends only to the metathorax, but is very 
large, surrounds the whole apparatus, and is externally bounded 
by a sharply defined arched line. Coreomelas and Legnotus 
have a highly developed, long, raised sprout-groove, extend- 
ing along the suture of the mesosternum, and terminating in 
L. picipes with a projecting tooth; the evaporating-surface 
is very large, and extends backwards, more or less sharply 
defined, over the metasternum, covers the whole suture of the 
mesosternum, reaches some distance beyond the mesosternum, 
and sends a continuation forward along the margin of the 
elytra. In Podops, Ailia, Cimex melanocephalus, vernalis, and. . 
baccarum, the opening is small, lateral, without a proper spout- 
groove; the evaporating-surface is extensive, and forms an 
oval spot which covers the suture between metasternum and 
mesosternum. In Strachia and the other members of the 
other Danish species of Cimices have a well-developed, long 
spout-groove, of which the external extremity is specially 
