1909.] NATURAL SCIENCES OF PHILADELPHIA. 329 



reduced in size. Neurocirri arise from beneath the base and rather 

 on the posterior face of the neuropodia, and have somewhat swollen 

 bases and a small, slightly distinct distal piece reaching about as far 

 as the end of the neuropodium. They are similar on all parapodia. 

 Notocirri arising from low swellings (but not distinct cirrophores) 

 on the dorsum well above the parapodia. Styles rather long, slender 

 and unjointed, but more or less wrinkled. The first (on II) is longer 

 than the others, about twice the dorsal peristomial cirrus and about 

 one and one- third the width of the segment; that of III is less than 

 two- fifths, of IV about three-fifths and of V about seven-eighths of 

 that of II; remaining notocirri are alternately longer and shorter, 

 those in the middle region being respectively about equal to three- 

 fifths and one-third the width of their segments. 



Neuropodial acicula generally two in anterior, three in middle 

 region, moderately stout, straight, tapered, the ends slightly knobbed. 

 Notopodial aciculum single, slender, gently tapered and curved, the 

 distal end slightly knobbed and often bent at the end. Neuropodial 

 setse entirely subacicular, in dense fascicles of several ranks, rather 

 numerous, usually ten or eleven ranks of three or four each. They are 

 colorless, rather stout, with curved stems becoming thicker distally 

 and ending obliquely in a blunt, slightly roughened point (PI. XV, 

 fig. 10). Appendages short broad blades varying in length only from 

 once to twice the width of the distal end of the stem, the longest occur- 

 ring in anterior parapodia and the ventral part of the bundles, termi- 

 nating in a prominent hook, well below which is a stout spur. In the 

 posterior region a solitary slender, curved simple seta also occurs in 

 each fascicle, but has not been detected elsewhere. 



A dissected proboscis exhibits the characteristic thick bow and fold 

 of the chitinous rim, but the number and character of the teeth is not 

 evident. The gizzard of the same specimen has sixty-seven annulations. 



Color pale yellow with a conspicuous spot on the prostomium, the 

 nuchal fold and narrow intersegmental transverse lines black; in the 

 middle and posterior regions every fourth one of the latter is much 

 wider and denser, and at these deeply pigmented furrows the frequent 

 fractures of the body- walls always occur; appendages colorless; 

 eyes brown. 



The label reads: "Phosphorescent annelids caught at surface, Avalon 

 Bay, Catalina Island, evening, April 11, 1904, Albatross." Professor 

 William S. Ritter writes that a phosphorescent annelid swarms at the 

 surface of San Diego Bay. Doubtless this is the species here described. 

 It is a frequent characteristic of species of this genus to be luminiferous. 



