1900.] FROM THE FALKLAND ISLANDS. 529 



his Eurypodius latreillii seems almost certain, because he does not 

 begin according to custom with a Latin, followed by an English 

 description of it, but with the explanation of the figures in the 

 plate, appending as usual more or less desultory descriptive obser- 

 vations. The explanation of the figures refers to plate 3. figs. l«-c, 

 without any mention of fig. d, which appears three years later in 

 the explanation of the Plates of the Atlas as representing the 

 " abdomen, enlarged two diameters." On Plate 3 of the Atlas 

 there is indeed an abdomen or pleon, enlarged two diameters, and 

 its last segment is subtriangular, or one might fairly say triangular ; 

 but there is no letter or number on the plate to show that the 

 figure belongs to Eurypodius latreillii, and it may, I think, be 

 argued that Dana assigned it at a venture to his latreillii and then 

 described the pleon of that species from it. 



According to Dana, " the posterior margin of the inter-antennary 

 cavity, next to the outer antennae, is reflexed downward " in his 

 septentrionalis and brevipes, but not so reflexed in his latreillii. 

 Tozzetti does not take any notice of this distinction, in which 

 Gue'rin's latreillii agrees with septentrionalis. 



In Eurypodius latreillii from the Falkland Islands there is on the 

 underside of the rostrum behind the cusps a groove ending in a 

 strong forward pointing hook, as described by Gruerin and indicated 

 in Tozzetti's figures, pi. 1. fig. 18 (latreillei) and pi. 1. fig. 9 (audouini), 

 as well as in Dana's pi. 2. fig. 7 a (brevipes), but not in his pi. 2. 

 fig. 6 a (septentrionalis) nor yet in his pi. 3. fig. 1 a (latreillii). 



The opinion of Miers that all the forms assigned to Eurypodius 

 prior to 1886 belong to a single variable species is highly probable. 

 It is unfortunate that he should have overlooked the discussion by 

 Tozzetti, on which his judgment would have been so valuable. 



Of two dried specimens brought home by Mr. Vallentin, the 

 larger is 52 mm. long from tip of rostrum to end of the carapace, 

 and 32-5 mm. broad at the widest part ; the carapace, excluding 

 the rostrum, is nearly 4-jL times as long as the rostrum. 



Pound clinging to the stems of Macrocystis. Mr. Vallentin says : 

 " I have frequently detected one of these crustaceans slowly re- 

 tiring to the root, as the stem of Macrocystis was being hauled into 

 my boat for examination, and if the rate of hauling was suddenly 

 quickened, one might possibly secure the specimen by making a 

 frantic grab at it before it slipped off. All the four pairs of ambu- 

 latory appendages modified to enable the animal to cling to this 

 weed." Gruerin fancied that they were modified for swimming. 



MACEUEA. 



AlOMALA. 



Section Lithodinea. 



1849. Lithodeacea, de Haan, Pauna Japonica, Crustacea, pp. viii, 

 xxii, 197, 213, etc. 



1850. Lithodina, Brandt, Bull, phys.-math. Acad. St. Petersbourg, 

 vol. viii. p. 54. 



