28 T. V. HODGSON. 



is rounded. The palp is three-jointed. The first is very small, the second large, cordate 

 in shape ; the third is a rather short and broad lobe, articulated nearer to the outer 

 portion of the second. The inner margin of the second joint and the extremity of the 

 first are richly clothed with simple setae. A few other small ones are scattered along 

 the other margins, and also irregularly over the surface of the entire palp, masticatory 

 lobe, and distal portion of the epignath. 



Eights' description of this organ is not easy to interpret exactly, but as far as 

 it goes it agrees with the above, except that a single tooth is only mentioned as 

 occurring on the masticatory lobe. As the second may be easily concealed by the 

 palp, this is of small moment. 



The descriptions given by Dr. Studer and Mr. Beddard are very concise. The 

 figure given by the former is very crude and incomplete, though fairly correct as far 

 as it goes. Mr. Beddard's figure is very much more correct and detailed. Only one 

 tooth is figured, the position of the second being covered by the palp. The basal 

 plate is, however, figured as being divided. I have not been able to detect the 

 existence of such a division even with a ^ objective ; bands of muscle interfere greatly 

 and render its determination difficult. 



The first appendage of the mesosome is subchelate and comprises six distinct joints, 

 the first of which is subequal in length to the last but one. The three following are all 

 very short, and two, the more distal ones, have a very irregular shape. These three 

 short joints all bear a tuft of somewhat specialised setae, which are numerous only on 

 the third of the joints, and this one, with the second, bears a number of very minute 

 teeth on its inner maro-in, the third having; in addition two stout teeth and a third 



O ' O 



much smaller one. The propodus is large and ovate in shape, its inner margin being 

 flattened to form a blunt knife edge and provided with a series of very highly 

 specialised structures, which have not been described for this species, notwithstanding 

 the fact that they afford valuable specific characters. Eights describes the margin of 

 this joint as ciliate. Dr. Studer remarks that it is provided with lancet-like teeth, 

 and figures five joints of this appendage, but on so small a scale as to be worthless. 

 Mr. Beddard does not refer to this appendage except in very general terms. The 

 specialised structures (figs. 7 and 8) consist of a regular series of stout teeth, and alter- 

 nating with them are leaf-like blades, both being obviously of a sensory nature. The 

 teeth have a strongly-marked " midrib," which, however, is not quite straight, and 

 terminates in a delicate elongate sensory structure. The blade is very faintly 

 striated, and terminates in an irregular manner, to allow r the sense organ to protrude. 

 The " leaf-like " organ also has a distinct " midrib," but the blade is very unequally 

 developed on the two sides, and exhibits a much coarser striation than the tooth. 

 The " midrib " terminates in precisely the same way and in a similar sensory structure. 

 Of the remaining appendages of the mesosome four progressively increase in size, the 

 second to the fifth ; this and the sixth are subequal in size, but the seventh is much 

 smaller, but in the larger of the ' Discovery ' specimens the greater part of most of these 



