242 GEORGE T. HARGITT. 



W. Hargitt's collection, but which he did not use in his paper on 

 variation. The extra tip is seen to be much shorter than the 

 main tip. Each tip is supplied with one of the suctorial pads, 

 but the shorter one arises from a point considerably proximal to 

 the pad on the main tentacle and directly from the tissue of the 

 tentacle. No sign of injury is present. The appearance of this 

 tentacle suggests the probable result of further growth of the 

 bud shown in Fig. 3, except of course the lack of the pad at the 

 base of the bud. Fig. 2, showing a trifid tentacle, is taken from 

 Hargitt's paper on variation (pp. cit.}. It shows two branches 

 arising from near the end of the main tentacle which seems to be 

 degenerate as mentioned later. The buds here do not seem to 

 arise from the suctorial pad of the main tentacle, which is not 

 shown, but each bud is supplied with a pad near its tip. The 

 knob on the tentacle under consideration, however, had more 

 the appearance of a bud than a bifurcation. This was due 

 chiefly to its small size which rather suggested that it was a very 

 early stage in the formation of an extra tip to the tentacle. 



The bud arose from a definite base which presented almost 

 exactly the same external appearance as the normal suctorial pad. 

 This similarity consisted not only in the smooth appearance, due 

 to the absence of the ectodermal ridges found on the other parts 

 of the tentacle, but also in its concave form, and the further 

 presence of a bend or " knee " in the tentacle at this point ; all 

 of which are characteristic of the normal suctorial pad (Figs. 

 3-5). The bud arose from a depression in the base (Fig. 4) due 

 to the cup-like shape of the pad already mentioned. 



No external sign of injury was found either in this pad or in 

 the surrounding tissue. The pad was of course not functional 

 as an adhesive organ, another functional one being present 

 nearer the distal end of the tentacle (Figs. 3 and 5). Whether 

 this new pad formed after the beginning of the development of 

 the bud from the old pad, whose functional activity would thus 

 be destroyed ; or whether a second pad formed first, and a bud 

 began to develop from the old one (which would not then be 

 necessary) simply as a result of the capacity for regeneration, or 

 rather duplication of parts, inherent in the tentacles, is an ex- 

 tremely interesting question. Of course no direct answer can be 



