HUNGERFORD: AQUATIC HEMIPTERA. 137 
pointed spine, apically and exteriorly, and some stout scattered spines in- 
teriorly, beginning half-way up to the tibia. The end of the tarsus ex- 
tends beyond the middle of the claws. 
“The abdomen and other details omitted are as in the first instar.” 
. Third Instar. 
“Size. Length 1.2-1.32 mm.; width .72 mm. to .8 mm. balsam amount. 
“Eroportions.of head: long: lat.) :: 238°: 35): eyes > vertex) :: 7 3,21): 7; 
antennal joints, 12 : 10 : 11 : 21; rostral joints, 6 : 6 : 19 : 9 (measured 
from cast nymphal skin) ; prothorax, lat. : long. :: 6 : 42. The antennze 
and legs grow comparatively slenderer, but the number of joints does 
not change. The cleft spine on the outer side, subapically, of the pos- 
terior tibie still persists. The other details omitted are as in the pre- 
vious instars.” 
“oy Fourth Instar. 
ze. 
wantennal jolts, 22 309): 10s 24: rostal joints, 7, 3°62 17": 9. 
“Owing to having nothing but moulted skins, a number of details 
must be omitted in this and the next stage of the nymph. The general 
form, aspect and coloration are as before, the main changes noticeable 
being in the increasing slenderness of the legs and antennez. In this and 
the preceding instars, the spiracles can be seen in the cast skins, 
_as little round openings in the connexivum. In the entire bug I have 
— 
not been able to locate them. The basal joint of the antenne is stout 
and curved, as before, and there is no change in the relative thickness 
among them. The other details are practically unchanged. The first 
pair of legs is the stoutest, especially as to the tarsi, and these are 
single-jointed in all the legs.” 
Fifth Instar. 
“Size. Length, 2.14 mm.; width, 1.25 mm. 
“Antennal joints, 20 : 13 : 13 : 35; rostal joints, 6 : 4 : 21 : 10. With 
slight differences, the other details are as before. The tarsi continue 
single-jointed, with long, simple claws, the posterior tibiz2 are spined 
toward the end, the spines increasing in number from the femoral to 
the tarsal extremity, and stout in proportions. The cleft spine mentioned 
before is still present, but is not so noticeable. In this instar, though 
still greenish in colour, with darker spots, lines and markings, the sil- 
very patches, so characteristic of the adult, first make their appearance. 
The female can in this instar be already distinguished from the male 
on account of its larger size, and less prominent genital segments. The 
males are so much smaller in this instar than the females, that they 
may be mistaken for nymphs in the fourth instar only. The dimen- 
sions of the nymph, taken from the cast skins, mounted in balsam, are 
not quite accurate, as the skins are much distorted.” 
Microvelia borealis Bueno. 
Habitat Bueno in his recent paper says it has a limited range, 
doubtless because little collected. He records it for New York, New 
Jersey, and says Parshley got it in Maine. The writer found it abundant 
on the margins of a little pool (Cattail pool) near Lawrence, Kan. 
This pool has dried completely for the past three summers, and it is no 
longer to be taken there. He found it in both the apterous and winged 
state, living upon the floating mats of Algze and dead Typha stems. It 
was also found at the Brick Plant pool in all stages in July and August. 
Hibernation. As an adult. 
