
552 THE AMERICAN NATURALIST. [Vor. XXXVI. 
SEASONAL ASPECTS. 
The seasonal range among medusz is noteworthy in many 
cases, both by reason of its periodicity in certain species and 
by its perennial character in others. The following are among 
the distinctively spring medusz. 
Hybocodon prolifer Ag. is one of the most restricted in this 
respect, ranging from late February to about the middle of 
May. It is one of the most beautiful and brilliant of the 
early medusa. Its proliferous budding of secondary medusæ 
from the large single tentacle is an interesting and well-known 
feature. I have also found it producing actinule from the 
walls of the manubrium at the same 
time. These seem to arise much as 
do similar larve, from several other 
anthomedusa, and a histological exam- 
ination shows essentially similar fea- 
tures of oógenesis and spermatogenesis, 
though there is no appreciable distinc- 
tion of sexes so far as morphological 
features are concerned. 
Tiaropsis diademata Ag. This is 
likewise an early medusa. According 
to Agassiz, “ one of the earliest visitors 
| of our wharves in spring.” During the 
present season it has been taken from 
March 20 to May 1, though only in 
limited numbers. 
Coryne mirabilis Ag. is also one of the earlier medusz, but 
with a longer range, from February to May. It has been 
reported by Fewkes as occasionally taken at Newport in 
early summer. 
Lizzia grata A. Ag. Of this medusa I have records during 
the present year from March 27 to April 29. Fewkes has 
reported it as occurring at Newport during the entire summer, 
but this would seem to be somewhat unusual. 
Tima formosa Ag. This beautiful medusa, one of the 
| largest of the early Hydromedusz, while not specially rare at 

Fic. 3. — Coryne producta. 

