ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 471 
eggs every time I collected this species during this period. This rather precisely 
? 
fixes the time when the females are “in berry.” They carry eggs during the 
months of April and May, but at no other time of the year, and during this season 
all females, with few exceptions, no matter whether they are large or small, have 
eggs. The smallest observed with eggs was 40 mm. long. Of course in the begin- 
ning of the spawning season larger females may also be without eggs, but later on 
females larger than 40 mm. long are only very rarely found without them. The 
latter generally are newly moulted (having soft or clean shells), showing clearly 
that at the beginning of the spawning season they were very likely below the mini- 
mum size for spawning. Of the few females under 40 mm. long none had eggs. 
During the spawning season (April and May) a general tendency toward moult- 
ing is observed in all specimens which are not females “in berry.” Among the 
sterile females, as well as among the males, the old, dirty shells disappear; newly 
moulted shells become more and more frequent, and soft shells are frequently 
observed. This moulting process in most individuals takes place in the first half of 
May, but, as we have seen, some individuals begin as early as March, and in others 
the process is delayed till the beginning of June. But by this time all specimens 
have moulted under normal conditions, with the exception of the fertile females, 
which moult after the young are hatched in June. 
A remarkable fact in the case of the males is that this spring moult farrartelblhy 
changes them to the second form.” In consequence males of the first form become 
scarcer and scarcer, till finally at the beginning of June all have disappeared and 
only males of the second form are left. Another remarkable fact is that after the 
end of the moulting season in spring no very large males are found. While large 
males of the first form of over 70 and 80 mm. in length are quite abundant in March, 
April, and the first half of May, they become very rare after that time, and the 
males of the second form, which are then abundant, only in rare instances exceed 
the size of 70 mm. in length, (only two cases on record). During the summer the 
males are generally less than 70 mm. in length. Large males reappear after the 
summer and fall moults begin, and then they are again of the first form. 
The question arises what becomes of the large males (over 70 mm. in length), 
which are rather frequent in spring. According to the records, we cannot assume 
that they moult into the second form, for we should then find large males of the 
second form in summer. Thus it is suggested that these large males die and disap-’ 
pear. Of this I have found positive evidence in two cases. On June 6, 1904, I col-, 
lected in the Shenango River at Linesville, Crawford County, a large male of the first 
°° This change was first observed by Faxon (1884a, p. 42) in Cambarus rusticus Girard. 
