52 THE AMERICAN NATURALIST. 
2. Variation in the Branchial Filaments of Aquatic Lepidop- 
tera Larve.1— The larvae of the Pyralid Paraponyx obscuralis 
from the Illinois River at Havana have just [always?] 100 
branched branchial filaments (gills) arising from the dorsum of 
the middle segments. The number of branches to a gill is 
modally different for the different gills, and for the corre- 
sponding gill in successive moults. In each gill of the full- 
grown larva, however, the number of branches is subject to 
individual variation. The following table gives the modal 
number of branches for each gill of the full-grown larva. 
SEGMENTS. a.s.? | LES | a.i. pi. ped. 
| EA EA E Bue 
js | 
2 6 | 5 3 5 6 
3 6 5 3 5 6 
4-7 4 6 4 5 5 
8-10 4 6 4 5 4 
II 4 6 4 5 
12 | 3 
| | 
Inheritance in Tailless Cats. — A female Manx cat (with ` 
rudimentary tail) had six litters by normal male cats. In these 
litters the number of abnormal (Maternal type) and of normal 
(Paternal type) kittens was as follows: 
Litter 1 LM 
"t Sarre? 
3M-t-2P 
IMF 
MERGE 
3M t-2P 
Aun pea N 
The maternal (Manx or abnormal) quality was prepotent. 
Also, there was a loss of this prepotency in the later litters. 
Was this due to telegony?—R. AwrHoNv in Bull. Soc. 
d Anthrop. de Paris, 4 sér., vol. X, p. 303, 1899. 
On the Entomology of the Illinois River and Adjacent Waters, 
te Lab. Nat. Hist., vol. iv, 149-273, 1895. 
? a. anterior; ., posterior ; s., suprastigmal ; ż., infrastigmal; ped., pedal. 
! Hart, C. 
Bull. Illinois Sta 
