STOLON FORMATION IN SPECIES OP TRYPANOSYLLIS. 411 
Stolon Formation in Certain Species of 
Trypanosyllis. 
By 
F. A. Potts, Itl.A., 
Fellow of Trinity Hall, Cambridge, and Demonstrator of 
Comparative Anatomy in the University. 
With Plate 23 and 23 bis and 8 Text-figures. 
Introduction. 
In 1896 a single .specimen of a Sjllid Polychiet was dis- 
covered by the Columbia University Expedition to Puget 
Sound, in which the reproductive individuals or stolons were 
produced from the ventral surface of the last two segments to 
the number of fifty or more, arranged in a compact rosette 
instead of such a linear chain as occurs in Autolytus or 
Myrianida. This was described by II. P. Johnson (1) as 
Trypanosyllis gemmipara. For another unique example 
exhibiting a similar phenomenon, collected by Harold Heath 
in California, he instituted the species Tryjiauosyllis 
ingens (3). Since then two other species have been dis- 
covered which reproduce in the same manner — 'I', m i s a k i e n s i s, 
by Izuka, in Japan (4), and T. crossland i, by Cyril 
Crossland, at Zanzibar, which is here fully described for the 
first time. 
Though the ])henomenon has thus been shown to exist in 
species of the genus Trypanosyllis from widely different 
parts of the world, it has never been found possible to obtain 
material in sufficient quantity for a thorough study of the 
phenomenon. In fact, only a single stolon-forming individual 
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