A REVISION OF THK DKLTOII) MoTIIS SMITH. 5 



but iK'coinpiiTiicd also in every case witli little tiil'ts of cilia' aiisin^- 

 ii'oiii small tubercles set into sensory pits of the nu)st diverse character 

 and varyin,u' j^ieatly in number. Often the Joints are clothed with 

 scales which are somewhat elevated at ti]) and so arrani^ed as to make 

 them seem serrated or marked at the edges, an appearam-e not borne 

 out by the Joints themselves when denuded. The bristles become 

 gradually longer, and are then reinforced by small piocesses or teeth 

 which are i)itted and give rise to sensory hairs. Usually there are 

 tubercles also, or little pegs set in large pits, and from these arise single 

 hairs or little tufts. The bristles gradually change to pectinations, 

 long or short, never more than one to each side of each Joint, and these 

 in turn are furnished with lateral ciliations, regular or irregular. Some- 

 times there is a stout bristle inserted near the tip of the pectination, 

 in a deep pit, a little protuberance on the branch giving additional 

 supi)ort. There is also considerable variation in the length of the 

 pectinations, and as they increase in length they usually become less 

 robust. Where they are short and stout additional tubercles or pits 

 with tufts or single hairs become more numerous. 



In addition to these normal structures of the antenna' there are others 

 that are decidedly unusual, always placed at about one-third from the 

 base. This abnormity may consist of a mere thickening of the scaly 

 clothing, the individual scales becoming larger in every direction, and 

 they may or may not cover a slightlj' enlarged Joint or two. Sometimes 

 beneath the tuft of scales one, two, or three Joints will have, in lieu of 

 ordinary pectinations, stout, short, pointed, straight or curved, brown, 

 corneous processes, two of -which are usually contiguous at tip, so as to 

 seem under a low-power hand lens the point of a single process. Where 

 such jtrocesses occur the Joints are often considerably broader and 

 sliorter and sometimes have numerous pittings with or without bristles, 

 hairs, or pegs. In such cases, also, the pectinations or lateral processes 

 of the antenme are wanting, or at least much abbreviated, on the inner 

 side from the base to this specialization. These processes attain their 

 maximum development in Zaiwhu/iKitha, aiidare always associated with 

 a pectinated or strongly bristled antenna, and with strongly tufted 

 anterior legs. Associated aiso with the modifications of the Joints there 

 is a greater or less marked change in the continuity of the antenna as 

 a whole, sometimes amounting to a distinct curve. 



In Tctanolita we have a distinct departure in a different direction 

 in the form of a pointed tuft of hair on the inner side, covering no 

 special modification save two slightly enlarged Joints. In Renia the 

 modification has assumed more definite form, and the tult becomes quite 

 prominent. AVe notice also that the antenn<e are more slender beyond 

 the tuft, that there is a tendency to curl, and that there seems to have 

 been quite a definite change in structure at the point covered b}' the 

 tuft. After ])roper prei)aration for study under the microscope this is 

 seen to be the fact, one of the Joints being much elongated and also 



