3G Prof. M'Intosli's Notes from the 



far as could bo observed, tlie general arraiiircinent and minihor 

 of the setigcrous and unciuigerous processes agree Mitli 

 tliose of P. aurantiacus. 



Tlie anterior setigerous processes, wliicli commence on 

 tlie second segment, appear to have a slightly longer posterior 

 panilladorsally tlian in the former species, but the bristles 

 are similarly arranged in a longer and shorter series, the 

 latter l)oing more numerous ventrally. The bristles are 

 devoid of wings, are translucent pale golden, and in lateral 

 view present a slight enlargement before tapering to the 

 delicate tip, which is slightly curved. The shorter forms 

 have a more attenuate hair-like tip, and also present a trace 

 of an enlargement belo'w it. The posterior bristles arc 

 shorter, more slender, and fewer in number in the small 

 tufts. 



The nneinigerous processes commence about the ninth 

 bristled segment, and occur iu a single row. Anteriorly 

 tlie hooks are small, have a much shorter base than in 

 P. niirantiuais. and the inferior outline rises into a con- 

 vrxitv behind the slender prow, while posteriorly it juts into 

 a process. Two or three teeth occur above the main fang, 

 and a distinct process projects from the anterior outline 

 just beneath it. The depth of the base posteriorly and its 

 abrujjt slope to the prow give a character to the hook. 

 Comparatively few seem to be in each row. 



The twenty-first form, Erentho smiiti, Malmgren, is 

 another extensively distributed species in which the cephalic 

 regujn is characterized by the absence of a distinct dorsal rim, 

 the smooth spout-like supra-oral fillet passing forward in tlie 

 niedian line, and, each side bending downward, forms a 

 })road rounded flap at the ventral edge, the arrangement 

 being svmmetrical. The external margin curves outward 

 and upward — almost to the dorsal edge, — then doubles 

 sharplv backward as a fillet and ceases. When the neck is 

 viewed from the dorsum these fillets are conspicuous on each 

 side. From the entire surface of this cephalic plate arise 

 the dense mass of bright yellow tentacles which form in- 

 extricable coils both in life and in spirit, and from the 

 edges of the lateral flaps are many small filaments. They 

 are mobile grooved organs caj-able of endless changes — 

 now flattened and again rounded, coiled and twisted in 

 various ways, or ajiain corrugated and wrinkled. The body 

 is pulled along by these organs which move like linear 

 IMemcrteans over the glass. The tentacles iu lifeshow a pale 

 central streak under a lens, and their sides arc dotted M'ith 



