ANTHOMEDUS.E SARSIA. 



51 



with long, tubular manubrium with the gonad confined to a short length near its free outer 

 end. He states that the Eximia group are represented by such forms as Sarsia eximia, 

 brachygaster, flarnmea, barentst, prolijera, angulata, and apiculata. The Tubulosa group are 

 represented by S. tubulosa, Jensa, decipiens, litorea, pulchella, frutescens, mirabilts, reticulata, 

 princeps, rosaria, etc. 



The genus Plotocnide Wagner, 1885, is defined by Hartlaub, 1907, as a Sarsia-Kks 

 medusa with nettle-cells upon the exumbrella. The gonad surrounds the manubrium from 

 the base downward. No ocelli. Hydroid unknown. It appears to me that unless it be 

 proven that the hydroid is different from Syncoryne, this genus should be merged with Sarsia. 



Weismann, 1881 (Zool. Anzeiger, Bd. 4, p. 61), shows that the circulation of fluids 

 within the gastrovascular cavity of Coryne pusilla is aided by the rhythmical contraction of 

 the walls of the gonophore. The systole and diastole are not always of equal duration, but 

 each ranges from 60 to 75 seconds. Thus the circulation in certain hydroids may be aided 

 by periodic peristaltic contractions as well as by the movement of cilia. 



Annandale, 1907, Journal and Proc. Asiatic Society of Bengal, vol. 3, finds Syncoryne 

 filarnentata, sp. nov., developing free medusae and growing in brackish pools of one-third 

 the salinity of sea water at Port Canning, Lower Bengal. The mature medusa is unknown. 



Tabular Description of the Medusa of Sarsia. Continued. 



