379 



Suh-order INCIRRATA, Grimpe 



Family ELEDONELLIDAE 



Eledonella massyae, Robson, subsp. purpurea, subsp. nov. 



St. 86. 24. vi. 26. 33° 25' 00" S, 6° 31' 00" E. 1000 (~o) m. 4 J m. tow net: one ?. 



Dimensions (in mm.). 



R. 



45 



This form is related more closely to E. massyae (Robson, 1924, 1924 a) than to the 

 other Atlantic or the Pacific forms. 



It differs in the following particulars: (i) The suckers (which attain a maximum 

 number of 10) are more widely spaced, viz. 6-5 mm. apart (as a maximum), instead of 

 4-5 mm. (2) The arms are a little shorter (54 instead of 56 per cent). (3) The funnel- 

 organ (Fig. 6) is longer and more angular. (4) The radula differs in several particulars. 

 In massyae the rhachidian bears three cusps on each side of the mesocone, the first 

 lateral five cusps on an average. In the new variety there are two cusps aside on 

 the rhachidian, and four cusps on an average on the first lateral. A still more striking 

 difference is in the size of the mesocone of the rhachidian, which is j\ of the base in the 

 type of massyae. In the new variety it is | of the base in length. (5) The gills are much 

 smaller in the variety, being about 9 per cent of the mantle in length, while those of the 

 type are about 16 per cent. (6) The colour is deeper and the chromatophores on the 

 head tend to fuse up to a very dark purple hue. 



Fig. 6. Eledonella massyae (right) and massyae, var. purpurea (left). Funnel-organs, x 7. 



This form is quite adequately distinguished from E. pygmaea, NernW, by the spacing 

 and number of suckers, the proportions of the arms and by the radula^ ; from B. diaphana 

 by its characteristic funnel-organ and the number and spacing of the suckers; and 

 from E. heathii, Berry, by the spacing and number of the suckers and the relative 



1 I assume that the radula figured by Thiele (19 15, p. 491) is correctly referred to Verrill's species. 



