2G 



AMERICAN HYDROIDS. 



86 



STUDIES OF LIVING SARCOSTYLES. 



Fig. 8G. Mesial nematophore of Af/laoplu'i'ia ftp , showing battery of nematoeysts with threads extruded. 



Fig. 87. Sarcostyle of riumtdaria phuiata entering the hydrotheca containing disintegrating hydranth. 



Fig. 88. Sarcostyle of PUitindarin pinnata entering a gonaDgiiini in which the gonophores have been destroyed. 



Fig. 89. Mesial nematophore of A : ilaoplienia helleri. ax, axial cavity of sarcost.yle ; ext, the terminal extensible process ; z( 2 , the extensible 



process which prqjrrts into the hydrotbeca ; n, batlery of nematocysts. 

 Fig. !)<>. Corbulu leaves of Aglnni>htnia jiliima, showing the sarcostyles holding the edges together, br, bridge formed between adjacent 



corbula leaves; sp, sarcodal pmc.essea. 



Fig. 91. Aniifboid cells found in the axial cavity of A. pluma, showing successive changes in outline during a period of two minutes. 

 Fig. 92. Mesial nematopbore of Antenninu janiiii in optical section, ax, axial cavity of sarcostyle ; eel, large ectoderm cells ; y, gland cells ( ?| ; 



n, nematocv.sts; p, perisarc; p', perisarc of stem. 



