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BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Gonosome . — Gonophores borne on shorter hydranths just below the tentacles and producing free 
medusae with 4 radial canals, 8 rudimentary tentacles, and neither mouth nor eye-spots. Ova borne 
on the very large manubrium. 
13 B. 
13. Stylaelis hooperi Sigerfoos. 
A. Nutritive hydranth or “person.” 
B. Reproductive hydranth or “person.” 
14 B. 
14. Pennaria tiarella McCr. 
A. Branch of colony. 
B. Hydranth with medusae (enlarged). 
C. Single sessile medusa (enlarged) . 
Color . — A specimen kept for some time in formalin is of a reddish flesh color. I have not seen 
the free tried usee, and the color is not given by the original describer. 
Distribution . — Found on shells of a living gasteropod, Ilyanassa obsolete/. A colony was found at 
Woods Hole in 1886. Dr. Sigerfoos found numerous specimens at Coldspring 'Harbor, Long Island. 
PENNARIDiE. 
Trophosome . — Colony regularly branched (in our species). Hydranths with a proximal circlet of 
filiform tentacles and a distal set of spirally arranged or whorled capitate tentacles. 
Gonosome . — Gonophores producing medusse which are either attached permanently or become 
free when mature, and which have 4 radiating canals and 4 rudimentary tentacles. 
