442 WILLIAM M. GOLDSMITH 
normally in the second. The bahavior, however, varies some- 
what in these forms. In Limoneus griseus, for example, the 
odd-chromosome, which is larger than the autosomes, lies later- 
ally and in advance of the other chromosomes in metaphase, but 
lags behind in anaphase and telophase. In the second division 
it divides later than the other chromosomes. In Necrophorus 
sayl the odd-chromosome passes to the pole in the first division 
simultaneously with the autosomes, but at the periphery of the 
plate; while in Chrysomela similis it passes laterally and in 
advance of the other chromosomes. 
Photinus consanguineus and P. pennsylvanicus are marked 
exceptions to all other forms, according to Stevens (’09). In the 
former the odd-chromosome divides late in the first division and 
passes to the pole in the second in advance of and lateral to the 
autosomes. The behavior of this body in P. pennsylvanicus is 
the same as in P. consanguineus, except that there is greater 
delay in passing to the pole in the second division. It will be 
noted that the behavior in these two forms would be identical 
with that in the type considered above were the maturation 
divisions reversed. 
Schafer (07) finds another variation from this third type in 
Dytiscus marginalis. He describes thirty-eight chromosomes 
in the spermatogonial and nineteen in each of the spermatocyte 
divisions. The odd-chromosome divides in both maturation 
divisions. ! 
Fernandez-Nonidez (’14) finds the odd-chromosome in Blaps 
lusitanica, attached to another pair on the first maturation 
spindle. 
The families Dytiscidae, Elateridae, Lampyridae, possess the 
single odd-chromosome. 
The following is a typical fertilization formula for these families: 
Photinus (Stevens, ’09) 
Sperm Egg 
9+(9+xX)=18+ X=19¢ 
.9+X)+9+X) = 18 + 2X = 20 9 
