vol. l.i Ritter— Davis. — Enteropnt astn . \\)\) 



the character of those of T. krohni; that is, they are produced 

 into a small number of broad, low, secondary lobes. These 

 lobes are, however, less prominent in our species than are those 

 of T. krohni. Still another distinctive point in the course of the 

 post oral ciliated baud is found in the posterior lateral lobe, 

 PI. XVII, Figs. 3 and 4. This, instead of projecting backward as 

 it does in several species, for example, in T. grenacheri, and T. 

 ritteri, projects forward as it does in the Bahama species of 

 Morgan. The lobe is, however, much more prominent in the 

 present species than in any other hitherto described. It is long- 

 elliptical, the attachment being at one end of the ellipse. 

 Although in general it is directed forward, it is at the same time 

 inclined distinctly toward the dorsal side of the animal. 



As is the case with several other species, the anus in this 

 tornaria is situated excentrically, and is considerably nearer the 

 dorsal circumference of the anal field. 



The notochord, like the gill pouches, arises at an unusually 

 early time in the larval life of this species. It could be clearly 

 made out in the living animal, as a forwardly directed outpocket- 

 ing at the anterior end of the esophagus, PI. XVII, Fig 5, n. c. 

 The nature of the broad shallow pocket shown in the figure 

 between the notochord and the anterior pair of gill pockets, we 

 were not able with the limited number of specimens available, 

 to determine. 



None of the other organs present anything noteworthy so far 

 as our observations have gone. One of the specimens obtained 

 was kept alive iu the laboratory two days, during which time 

 metamorphosis distinctly" set in. At the time of its death seven 

 pairs of gill pouches were present, but none of them had yet 

 broken through the ectoderm, nor had the tongue bars developed 

 on any of them. The proboscis had become clearly marked off 

 and its musculature had begun to develop. No intimation of 

 the collar region was yet visible, however, and the ciliated girdle 

 was still present. The mesoblastic pouches, situated as in most 

 species, far back in the earlier larval stages, already occupied 

 positions relatively considerably farther forward, though the 

 anterior pair had not yet reached the anterior end of the series 

 of gill pouches. 



