296 THE AMERICAN NATURALIST. | [Vor. XXXVI. 
The worm is much flattened in the horizontal plane, measuring 
only 2 mm. in its greatest dorso-ventral diameter. The para- 
podia (Fig. 1) are very diminutive for the size of the trunk, and 
the somites are so short that the stout dorsal cirri (inasmuch 
as their thickness exceeds the length of the somites) form an 
alternating series. The somites number nearly 500. 
As Trypanosyllis ingens is undoubtedly new to science, a 
diagnostic description, with figures sufficient for its identifica- 
tion, is given. It is unfortunately too rare to serve as a 

BiG); — Anterior: Separadas rypanosyllis in, The palpi, antennæ, median cirrus 
peristomi and all the d cirri, och cus one enti, are broken off at the basal 
sui. x A ., peristomial cirri ; d.c., dorsal ci 
subject for study of collateral budding. It occurs in none of 
the numerous gatherings of Pacific coast Polychzta that came 
into my hands during six years' residence in California; and 
Dr. Heath, who has done a great deal of collecting at Pacific 
Grove and vicinity at all seasons of the year, informs me that 
he has found only this specimen. 
Trypanosyllis loge Sp. nov, 
Form elongated, broad, much depressed ; dorso-ventral differ- 
entiation very slight, dorsum slightly convex, ventral surface 
plane, longitudinally bisected by a narrow median welt, sharply 
bounded by two fine parallel grooves ; extremities evenly and 
abruptly rounded off; slightly more tapered posteriorly than 
anteriorly ; somites very short, crowded, about 476 in number. 
