EEEANTIATE POLYCHAETA OF JAPAN. 49 



Misaki, on April 2nd, 1905, and was kept alivo in a vessel for 

 a few days. It carried a mass of embryos nnder the elytra, from 

 the 8th posteriorly to the penultimate segment. On April 4tli 

 some of the embryos began to swim about freely in the vessel, 

 leaving the shelter of the mother. At first the free-swimming 

 embryos were in an early trochophore stage, exhibiting a weakly 

 developed ring of cilia, but soon this developed into the charac- 

 teristic state that enabled the larvae to swim about very 

 actively. 



Harmothoe yendoi n. sp. 



PI. V, figs. 5—8. 



An unique specimen of this species was obtained by Mr. 

 K. Yendo in July 1903, at Shimushu, Kurile Is. It was found 

 on Arshro hifidvs that was brought up from a depth of 4 fathoms. 



On careful examination the specimen was found to differ 

 from tlie foregoing species in some important characters, though 

 there existed n general agreement in the features of l)ristles, in 

 th(! peculiar position of anterior eyes, and in the relative lengtlis 

 of tentacles and subtentacles. 



Compared with tyi^ical //. imhrlcaia, the prostominm (fig. 5) 

 is more angular and tlie posterior pair of eyes placed at a more 

 mesiad ])Osition. The basal ])ortions of the median tentacle and 

 of tentacular cirri are quite stont in proportion to their slen- 

 (](')• Hhsdes; the swellings or bulbs at the base of their terminal 

 liliforin portions are vci-y slight : tlie ends of subtentacles are 

 greatly attenuate(l and finis foi'in filiform terminal pieces like 

 tliose of the tentacles (^r tentacular cirri. 



The dorsal cirrus is of a similar length as that of //. im- 



