682 SIR c. ELIOT ON NUDiBRANCHs [June 19, 



corners, as in many Aeolids. The formula of the radula is 

 47 X 20.1.20, increasing in a few rows to 23.1.23. 



B. The larger of the two specimens is bent, but about 25 mm. 

 long and 15 mm. wide, the margin being spread out. The colour 

 is grey ; the under sui'face, and especially the side-lamellpe, darker. 

 Most of the external characters in both specimens are the same as 

 in A : the globular body behind the branchiae, the anterior groove 

 and corners of the foot, and the parts in front of the rhinophores. 

 But the dorsal surface appears very different, since it bears 15-20 

 ridges divided by smooth areas. These ridges are formed of 

 tubercles more or less fused together. They are all small com- 

 pared with those of A, but in one of the specimens they are larger 

 than in the other, less fused together, and some bear spots as in 

 A. The two specimens do not agi'ee in details, showing that there 

 is a considerable tendency to variation. The radula in the 

 specimen opened is about 42 x 16.1.16 as a maximum, but many 

 I'ows are shorter. I propose to call this form L. variolosa, var. 

 striata. 



C. One rather large specimen, yellowish with traces of red and 

 brown here and there. Not so well preserved as the others and 

 rather soft. Length about 60 mm., breadth about 27. The 

 external characters are mostly the same as in the other specimens, 

 but the organ behind the branchiae is less globular and more 

 clearly resembles a swollen lamella. The greater part of the back 

 is covered with large and small tubercles as in A, the larger being 

 pitted at the top and having a diameter of about 2 mm. But in 

 the median part of the anterior half these tubercles give place to 

 ridges like those found in B, composed of small prominences more 

 or less fused together. The formula of the radula is 63 x 25.1.25. 

 In a few rows there are 27 laterals. 



The character of the dentition and jaws is the same in all the 

 specimens. The median tooth is broad, and bears 8-9 denticu- 

 lations and ridges on either side of the central cusp, which has 

 itself one or two small denticulations. In specimen A this 

 centi'al cusp is lower than in the others. The first lateral bears 

 about 8 denticles on the outer side. The second lateral also bears 

 about 8 denticles, and has something of the clumsy shape shown 

 in Bergh's plates {I. c. plate ii. figs. 17-20). The third lateral is 

 more erect, and bears about 4 denticles (rarely 5-6) near the top, 

 and often one or two more arranged irregularly lower down and 

 sometimes quite near the base. The fourth lateral bears one or 

 two denticles, rarely three. The remaining teeth are smooth and 

 hamate. The jaws are large, strong, brownish yellow, and bear 

 5-6 rows of knob-Hke dentitions along the edge. 



In Bergh's specimen only three laterals were denticulate, 

 whereas in all which I examined the denticulation extended to 

 the fourth tooth. This difierence, however, hardly amounts to a 

 specific character, unless it be found to persistently accompany 

 other peculiarities. The proper description of the radula is 

 probably : the first few laterals denticulate, the rest smooth. 



