Bie E 
AMERICAN NATURALIST 
VoL. XXXII. April, 1898. No. 376. 
THE SARCOSTYLES OF THE PLUMULARIDÆ.! 
C. C. NUTTING. 
THERE is no little confusion regarding the nomenclature 
involved in morphological discussions concerning the Hydroida, 
and nowhere is this fact more evident than in connection with 
certain interesting structures found in the Plumularide and 
variously called nematophores, protoplasmic processes, defen- 
sive zooids, sarcodal processes, Machopolyps, ‘‘Wehrthiere,” and 
Nesselpolypen by the numerous writers who have investigated 
them. The first mention that I have been able to find of 
these structures is by Busk in Hunterian Lectures (MSS.), 
London, 1857, who called them “ Nematophores,’ —a name 
subsequently used by various writers. Hincks afterward ap- 
plied the name “ sarcotheca” to the chitinous receptacle, and 
“sarcostyle’’ to the sarcodal contents, or rather defensive per- 
sons, inclosed within it. Without further discussion on this 
point, I will state that I use the word nematophore for the 
receptacle without necessary reference to its contents, and sar- 
costyle for the organ or person within, and it is to the latter 
that I invite attention at present. 
1 Read before section F at the Detroit meeting of the American Association 
for the Advancement of Science. 
