226 ABYLOPSIS ESCHSCHOLTZII. 



terior nectosac has been well described and figured by Gegenbaur ('60), and 

 the importance of this character has recently been emphasized by Lens and Van 

 Riemsdijk. The present series show it very well (Plate 14, fig. 7). There is 

 no variation from the typical arrangement in anj- of the specimens. 



The free Eudoxids have often been described, and Lens and Van Riemsdijk 

 have pointed out the differences between them and those of .4. eschscholtzii. 

 These consist, it is true, chieflj' of minor particulars in the form of the bract; 

 but they are so constant that it is easy to distinguish the two species. The 

 most diagnostic feature is the outline of the dorsal facet, which is a regular 

 pentagon in eschscholtzii, but subrectangular in tetragona. The ventral facet 

 is basally deeply convex in the former, straight in the latter; and the basolateral 

 facets also differ in proportions. (Compare Plate 15, fig. 7 with fig. 2.) 



Abylopsis tetragona is common in the Mediterranean, in the Tropical 

 Atlantic, where I have taken it among the West Indies, in the Malaysian 

 region, and over the entire region covered by the present cruise of the "Alba- 

 tross." It is also known from the Indian Ocean (Huxley). 



Abylopsis eschscholtzii (Huxley). 

 Plate 14, Figs. 1-5; Plate 15, Fig. 1. 



Aglaisinoides eschscholtzii Huxley, '59, p. 60, pi. 4, fig. 2; Chun, 'SS, p. UGO; Lens and A'an Riems- 

 dijk, :08, p. 25, pi. 3, fig. 18-31. Eudoxid. 



Abylopsis quincunx Chun, '88, p. 1160; Bedot, '96, p. 375. 



Abyla (Abylopsis) quincunx Chun, '97b, p. 29. 



Aglaisinoides quincunx Chun, '97b, p. 29. Eudoxid. 



Aglaisma quincunx Aoassiz and Mayer, '99, p. 180; Mayeu, : 00, p. 78; (non Agas.siz and Mayer, :02, 

 p. 164, pi. 10, fig. 45). Eudoxid. 



Aglaisma cuboides May'Er, :00, p. 77, pi. 30, fig. 104 (non Leuckart). Eudo.xid. 



Abyla quincunx Mayer, :00, p. 78, pi. 34, fig. 115-117, .\gassiz and Mayer, :02, p. 163, pi. 11, fig. 

 46, 47; Lens and Van Riemsdijk, :08, p. 21, pi. 3, fig. 22-27. 



Abyla tetragona Schneider, '98, p. 89 (partim). 



Abyla peniagona May'er, :00, p. 77, pi. 30, fig. 101-103 (non Eschscholtz, Chun). 



Chunia capillaria Mayer, :00, p. 78, pi. 27, fig. 90. 



The polygastric state of this species was captured at Stations 4592, 4594, 

 4613, 4637, 4646, 4659, 4665, 4673, 4687, 4707, 4715, 4732, 4734, 4737; the 

 total number of specimens being 25. The largest anterior nectophore is 5 mm., 

 the largest posterior one 8 mm., and the largest Eudoxid 5 mm. long. The 

 records are both from the surface and from open hauls between 300 fathoms 

 and the surface. The free Eudoxid was taken only at Stations 4671, 4673, 

 and in Acapulco Harbor, a total of four specimens. The union of this Pacific 

 series with the Atlantic species, rests not only on the similar identification 

 by Lens and Van Riemsdijk (:08), but on actual comparison of specimens from 

 both oceans. 



