i3S 



CRUSTACEA .MALACOSTRACA. III. 



The species has suffered from a peculiar fate. It is difficult to understand why Walker referred 

 it, with a query, to Munnopsis, as a glance at his figure of the male shows that the animal stands 

 far apart from that genus. Tattersall not only followed Walker, but even dropped the query; it is a 

 new, interesting case that a wrong opinion not infrequently acts as a suggestion, so that a successor 

 accepts it without critical consideration. Stepheusen, who believed that the species established by him 

 as Munneurycope Tjalfiensis was closely allied to but differing from M. Murrayi Walk., saw correctly 

 that it could not remain in Munnopsis, and therefore he established a new genus for its reception, but 

 neither in 1913 nor in 1915 was he aware that it would be difficult to point out any character worthy 

 to be considered of generic value between his new genus and Eurycope. In his first-named paper 

 Stephensen referred the forms Munnopsis longicornis H.J.H. and M. oceanica Tatt. to his new genus 

 Munneurycope, but in 1915 he removed these two species, so that Munneurycope should only comprise 

 M. Murrayi Walk, and M. Tjalfiensis Steph. 



Before entering on the question whether M. Tjalfiensis is a synonym to M. Murrayi or a sepa- 

 rate species, we may examine some features in order to judge of the validity of the genus Munneu- 

 rycope. In 1915 Stephensen published a good number of new figures of his M. Tjalfiensis. The first 

 autennular joint is somewhat longer than broad, while in most, but not in all, species of Eurycope it 

 is broader than long; furthermore, and what is of more interest, the joint in M. Tjalfiensis has no 

 produced antero-lateral part, but in this respect it agrees with the joint in E. nodifrons n. sp. Conse- 

 quently the outline of first antenuular joint does not afford any generic character. As to the shape 

 of the body, the anteunulse, antennae, mandibles, maxillipeds, thoracic segments and legs — as far as 

 these are known — M. Tjalfiensis agrees in every point worth mentioning with Eurycope. The uropods 

 have the exopod extremely small as compared with the endopod, but in several species of Eurycope 

 the exopod is somewhat or considerably shorter than the exopod. The lateral plates of the male oper- 

 culum show a difference, as the big coupling hook in M. Tjalfiensis (fig. 7 b) originates at the trun- 

 cate, nearly transverse end of the plate, while, f. inst, in E. inermis (PI. XIII, fig. 2 h) the postero- 

 interior angle of the plate is cut off in a way so that the margin where the hook is seen in reality 

 is the somewhat oblique terminal part of the inner margin of the plate. Finally, the penultimate pair 

 of pleopods have the exopod narrow with the end acute in several species of Eurycope, while it is 

 broader, obtuse, lamellar in M. Tjalfiensis, but unfortunately it is unknown in some species of Eury- 

 cope. All differences observed have been enumerated here, and I suppose that Carcinologists may 

 agree that Munneurycope cannot be maintained. But still one particular may be mentioned. Stephensen 

 pointed out an antennal scale in his species and added: "This last feature has not, as far as I am aware, 

 hitherto been found in any Munnopsid"; the antennal squama, however, had been figured and men- 

 tioned by me in 1887 ("Dijmphna-Togtet") as found in Eurycope giganti a. 



Then the question on the validity of E. Tjalfiensis as separate from E. Murrayi. In 1915 

 Stephensen enumerated four differences between his own animals and the descriptions and figures of 

 Walker and Tattersall. His animals had "a blackish brown or dark colour'', which he thinks is a 

 specific character, because this unusual colour was not mentioned by the two English authors. It is 

 true that Walker said nothing on the colour, but the description had been published more than four 

 and a half years after the capture of the specimens, and I suppose that they had been preserved al- 



