800 Wisconsin Academy of Sciences, Arts, and Letters. 
Though there was some variation in the position of the appen¬ 
dages, the male’s second legs (those next the chelipeds) were 
always hugged again the female’s hack, his third pair were be¬ 
tween the bases of her last two pairs of legs, and his abdomen 
was inside hers. Two males grasped the eyestalk of their mate 
with the small cheliped, the other three pressed that appendage 
on her back as shown in the figure. The great chela, was never 
pressed against the female, but was supported on the male’s sec¬ 
ond leg. The time of the different copulations was as follows : 
Fig. 7. Uca pugilator. A pair copulating. Drawn from life by Miss 
Barbara Bradley. 
July 15, 7 :00-7 :10 p. m.; July 23, 6 :35—7 :27 p. m.; July 24, 
4:40-4:53 p. m.; July 29, 8 :35-9 :1'0 pi. m.; July 30, 8 :38-9 :10 
p. m. In no case was the entire process observed; either the 
pair were already clasped when discovered or they were inter¬ 
rupted before they had finished. It will be observed that copu¬ 
lation took place in the afternoon or evening, but this may have 
been due simply to the quiet in the laboratory building at such 
time. All the females observed in copulation were “hard 
shells,” hence mating in fiddlers does not follow ecdysis as in 
some crabs. 
Summary. 
1 . Uca pugnax usually occurs on mud or clay bottoms; U. 
pugilator is commonly found where the beach is sandy. 
2. The females of U. pugnax were carrying eggs during the 
