LIMNOCODIUM IN THE UNITED STATES. 



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Several things might conspire to emphasize or exaggerate it. As 

 is well known, age has much to do with the shape of hydrome- 



FiG. 2. Medusa, floating aspect. 



dusse, young specimens often being hemispherical, while at matu- 

 rity they may become quite disc-like. Again, there are often 

 marked individual differences which have to be considered in 

 estimating the mean shape of the species. Further, preserved 

 specimens are almost always more or less contracted, and hence 

 may seem to be much more highly arched than is the case in life. 

 It should be observed in this connection that the specimens 

 shown in the figures present very different aspects. Fig. 1 repre- 

 sents the medusa in an average swimming attitude, the tentacles 

 more or less contracted, the manubrium somewhat contracted, 

 and the bell rather higher than shown in Fig. 2, which represents 

 the creature in the floating attitude, body and organs generally 



Fig. 3. Medusa, resting normally on bottom of aquarium. 



