MUSEUM OF COMPARATIVE ZOOLOGY. 15 



of its anatomy is easy. The following notes are the result of a careful 

 dissection of several specimens. The soft parts are mostly of a translucent 

 whitish color. The number and disposition of the muscles are similar to 

 those of W. australis, already described by various authors. The muscles 

 themselves are of a glistening tendinous appearance, except at their points 

 of attachment, where they are of a more or less dark yellowish-brown. 

 The peduncle is moderately long, and the portion which is external or 

 contained in the foramen is covered with a dark, horny reddish-brown 

 membrane or skin, and the attached extremity is trumpet-shaped. Upon 

 opening the shell in its normal position, the median spires of the brachia 

 are seen to be somewhat widely separated, and between them is stretched 

 a fine translucent membrane extending forward from the under lip of the 

 mouth and following the downward curve of the median lobes. In this 

 great extension.of this membrane this species differs from T. caput-serpenlis 

 and W. australis, in which species the cirrhi of the median lobes touch at 

 their extremities, and are separated by only a very narrow strip of mem- 

 brane between their bases, so that the appearance is almost as if there was 

 but a single broad band of cirrhi in the median line. This intervening 

 membrane in ordinary specimens of W. floridana is about .24 of an inch 

 in width at its narrowest visible portion. The upper and lower bands of 

 cirrhi in the lateral loops are also much more widely separated by a similar 

 membrane, than in W. australis. The reason of this appears in the 

 fact that the brachial band follows the outer edge of the apophyses in both 

 species until it curves downward in the middle, and the shelly portions of 

 the apophyses in W. floridana are very much wider than in W. australis ; 

 hence the greater separation. The longest of the brachial cirrhi, in front, 

 measure about .14 inch in length ; those of that part of the band which 

 passes behind the mouth are about the same length. Th6y are, as in other 

 species, disposed in a double row, the cirrhi of one row being opposite the 

 spaces of the other. The spiral portion in the middle lobe makes about 

 two complete turns. With regard to their disposition and the manner 

 in which the cirrhi are set upon the brachial band, I can add nothing 

 to the observations of Mr. Hancock, with which my own agree in every 

 particular. A series of transverse lines at regular intervals was observed 

 on the individual cirrhi, somewhat resembling in appearance the trans- 

 verse markings on the setae. The mouth is, as usual, just in front of the 

 posterior junction of the brachial bands, and is in a rather long flexuous 

 groove, the edges of which are of a dark brown color, and somewhat 

 thickened. The upper or posterior lip, if such it may be called, has a for- 

 ward prolongation or convexity in the median line, to which a slight con- 

 cavity or indentation in the lower lip corresponds. The oesophagus is 

 about half as long as the intestine, and has a slight curve, of which the 



