490 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.45. 



The second point of divergence of my results from Herdman's 

 description concerns the tentacles. These are said by Herdman to be 

 all of one size in japonica; and in his schematic classification of the 

 species of Corella, given on page 190, he makes this the final criterion 

 for differentiating japonica from eumyota, the last being characterized 

 by tentacles of two sizes. In all the specimens examined by me the 

 tentacles are at least of two sizes, and although the difference, par- 

 ticularly in length, is not great, it is undoubted. And an interesting 

 fact about the difference is that, particularly in some individuals, 

 the larger tentacles are bent in toward the center of the circlet — 

 that is, toward the branchial orifice — distinctly more than are the 

 smaller ones. This difference in disposition of the tentacles of differ- 

 ent sizes is especially observable in one of the individuals from 

 Yokohama sent me by Hartmeyer. 



Figure 30, showing the arrangement of the stigmata in one of my 

 specimens, corresponds so well with Herdman's figure 5, plate 26, 

 as to leave no doubt about the agreement in this regard; but the end- 

 to-end and reversed dispositions of the openings as here seen is 

 worthy of particular notice since this seems to afford one of the best 

 distinctions between C japonica and O. sequahilis Sluiter (Sluiter, 

 1904, p. 17), end-to-end arrangements of the stigmata in the same 

 infundibulum not occurring in Sluiter's species. 



Concerning C. japonica and 0. eumyota, as our information now 

 stands the best differentiating marks are the larger number of bran- 

 chial tentacles and the greater irregularity and the different modes 

 of coiling (Herdman, 1910) of the stigmata in eumyota. The differ- 

 ence in the mantle musculature and the size of the tentacles, especially 

 appealed to by Herdman, do not seem to hold, at least on the ground 

 on which he placed those differences. The statement by Traustedt, 

 1882, page 285, that C. japonica is distingished from C. eumyota by 

 papiilse on the internal longitudinal vessels of the former and their 

 absence in the latter is due to error on Traustedt's part, papillae not 

 being present in japonica. 



Five specimens from Albatross 3656, Hakodate Bay, Japan, 11.5 

 fathoms, gn. m. s. 



Three specimens from station 3659, Hakodate Bay, Japan, 15.5 

 fathoms, /we. gy. s. 



Both lots taken September 19, 1896. 



CORELLA, species. 



At Albatross 3088, off the coast of Oregon, a single specimen of 

 a Corella was taken which, though sufficient to enable one to deter- 

 mine with certainty the genus to which it belongs, is not sufficient 

 to warrant a decision as to the species. 



