544 Notes from the Gatty Marine Laboratory. 



terminal region. The translucent vacuolated hypoderm (or 

 other tissue) surrounds this fibrous axis, and its strands 

 occasionally give a quasi-pinnate aspect to the structure. 

 Some of the papillae have black pigment-grains scattered near 

 the tip and thinly for some distance downward, but they do 

 not seem to have any definite arrangement. Occasionally a 

 short cylindrical mass is extruded at the tip, the distal end 

 having a globular body within a sheath, and the basal having 

 a central tubular connexion with the tip of the papilla. A 

 thin cuticle envelops all, and it is thicker on the narrow 

 terminal part of the papilla. The cylindrical tip is often 

 truncated, the terminal fibres occasionally projecting beyond 

 it. No other termination to the process has yet been 

 observed. Sand-grains adhere to tin- bases and sides of these 

 organs, the exact nature of which is still subjudice. Other 

 papillae of the ordinary clavate character and coated with 

 sand-particles are also present on the general surface. 



The dorsal bristles are few in number, some bundles con- 

 sisting of two, inconspicuous and slender. They are pale 

 delicate bristles, with closely arranged articulations at the 

 base, somewhat irregular longer ones in the shaft, whilst the 

 joints increase in length toward the finely tapered tip. These 

 bristles are situated close to the ventral series and in the line 

 of the acuminate papillae. The dark yellow ventral hooks 

 (PI. XII. a. fig. 10) are of great length and nearly of equal 

 breadth to the commencement of the pale tip, and crossed by 

 closely arranged striae which are slightly oblique. These 

 disappear toward the translucent tip, which, as it narrows, 

 bends backward, and then, with a bold forward curve, ends 

 in a hook. The great length and linear arrangement of these 

 organs must give them considerable power, especially when 

 their own muscles and those of the remarkably muscular 

 and tough body-wall are considered. The setigerous lobes 

 supporting the ventral bristles are much less distinct than in 

 13. granulata, very few presenting the rosette-like arrange- 

 ment of the papillae of that form, the ventral division generally 

 being enveloped by the irregular lobate sandy masses pro- 

 jecting from the surface. This does not seem to be the 

 Brada inliabilis of H. Rathke. 



The question may be raised as to whether this form is not 

 a variety of Brada granulata, Malmgren, but the approxi- 

 mation of dorsal and ventral divisions of the foot and the 

 structure of the tip of the ventral hooks, which in some 

 are peculiarly attenuate, almost probe-like, distinguish it. 

 Again, if the flattened papillae should, on further investigation, 

 be found to be adventitious, then separation wuuld be less 

 necessary. 



