BY N. A. COBB. 395 



rows of alternating light and dark, uniform, rectangular, elongated 

 markings. This is a feature common to Chromadora and a few 

 other genera. Whether these markings are always uniform in 

 Chromadora is open .to question. It has been proposed that 

 where the markings are not uniform, that is to say are different 

 on the lateral fields, the species should be reckoned as a Spilophora, 

 provided of course that the worm presents the other features 

 characteristic of Sjnlophora. The idea is a good one, but certain 

 differences in the markings on the lateral fields are to be found 

 even in Chromadora, and it remains to be seen to what extent 

 this difference may develop in the genus. The cuticle of C. minor 

 bears in general none but most inconspicuous hairs, the cephalic 

 and subcephalic seise of course excepted. The neck is conoid to 

 the truncate head, which bears, opposite the ])haryngeal tooth, a 

 seta on each submedian line, four in all ; these setae are acute, 

 arcuate, and about half as long as the head is wide. Farther 

 back, namely, opposite the eye-spots soon to be described, occur 

 eight subcephalic setae, a pair being arranged one in front of the 

 other on each submedian line. The lip region is transparent and 

 the arrangement of the lips is difficult to make out. I believe, 

 how^ever, that three obscure confluent lips exist and that each 

 presents about four longitudinal striations, and furthermore that 

 these striations are the optical expression of a dozen chitinous 

 processes which might almost be denominated teeth, or at least 

 biting organs. Each lip presents two papillae on its anterior 

 surface. The pharynx may be said to extend almost as far 

 back as opposite the eye-spots ; in the formula, however, I have 

 measured only to the tooth which exists on the dorsal side of the 

 pharynx. This small tooth is hook-shaped and points forward ; 

 it serves to give the worm a grip on its food by acting in oppo- 

 sition to the lips and their chitinous processes. The position of 

 this tooth is, as already stated, dorsal. I empha.sise this because 

 I have seen specimens in which this tooth appeared to be ventral. 

 In fact, I was very near describing one such specimen as a 

 Hypodontolaimus ot de Man. The appearance is highly decep- 

 tive, and therefore worthy of description. The worm by an exact 

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