Kinsey: The Genus N euroterus 
65 
galls to determine the source of each insect. I found, in sev- 
eral instances for each species, both the Plagiotrichus and 
Neuroterus in both kinds of galls! Here is a case of gall 
dimorphism to match the several others in the genus, where 
the gall-producing capacity of the primitive N euroterus is 
not sufficient to obscure the nature of the plant tissue in- 
volved, and where the form of the gall thus varies as different 
plant tissues are attacked. But in this instance the inter- 
pretation is remarkably substantiated when we find two 
insects of distinct, but in both cases primitive genera, pro- 
ducing quite identical galls when the same part of the plant 
is attacked. It is possible that no other part of the plant 
but the ament and particularly the anther would restrict the 
gall as closely to form. The egg-shaped anther gall is now 
known from a number of species of Cynipidse of diverse 
genera (see the discussion of gall polymorphism in the intro- 
duction), and there seems to be little chance of the anther 
ever producing any other type of gall. This comparative, 
taxonomic study of species is giving us considerable informa- 
tion as to the factors which influence gall production. 
Neuroterus vernus variety tectus 
bisexual form tectus Bassett 
Neuroterus tectus Bassett, 1900 (in part), Trans. Amer. Ent. Soc., 
XXVI, p. 331. Dalla Torre and Kieffer, 1902, Gen. Ins. Hymen. 
Cynip., p. 51. Beutenmuller, 1904, Bull. Amer. Mus. Nat. Hist., XX, 
p. 26; 1910, Bull. Amer. Mus. Nat. Hist., XXVIII, p. 126, pi. XU, 
figs. 1, 2. Beutenmuller in Smith, 1910, Ins. N.J., p. 599. Dalla 
Torre and Kieffer, 1910, Das Tierreich, XXIV, pp. 337, 801, 835. 
Thompson, 1915, Amer. Ins. Galls, pp. 5, 13, 41. Viereck, 1916, 
Hymen. Conn., p. 389. Felt, 1918, N.Y. State Mus. Bull., 200, p. 
56, fig. 53 (1, 2). Britton, 1920, Conn, Geol. and Nat. Hist. Surv. 
Bull., 31, p. 320. Cresson, 1923, Trans. Amer. Ent. Soc., XLVIII, 
p. 203. Insects of both generations are involved in the above ref- 
erences. 
N euroterus tectus form tectus Kinsey, 1920, Bull. Amer. Mus. Nat. Hist., 
XLII, p. 339, pi. XXX, figs. 20-22. 
FEMALE. — Mouthparts light piceous; antennae brown, the second 
and third segments brownish yellow; abdomen higher than long, ex- 
tending ventrally almost as far as or slightly further than dorsally; 
legs light yellowish at the joints and on the tarsi; areolet small, aver- 
aging a little smaller than in exiguus; radial cell rather narrow; length 
0.6-0.9 mm. 
5—25671 
