EUCHAKTOMERA TYPICA. 199 



spine included; the penultimate pair of spines consideraljly longer than the 

 terminal pair, twice as lony; as tlie antepenultimate pair and nearly as long as 

 the breadth of the telson at their insertion. 



Length of both sexes 6.4 mm. 



Remarks. — This species is a little smaller than G. iiulicus, but so closely 

 allied that it might be considered a variety if it did not show the very marked 

 difference in the third pair of male pleopods; the rather short, triangular process 

 turning essentially outwards from the thick basal part twice as long as broad 

 seems to be an excellent specific character, as this part differs very much in 

 aspect from the corresponding portion in G. indicus, in which the thickened 

 part is much shorter and the process much longer and directed much backwards 

 or parallel with the exopod (Siboga-Exp., PI. 8, figs. 2k and 21); unfortunately 

 the distal part of that exopod is wanting. The peduncles of the three anterior 

 pairs of pleopods are more slender than in G. indicus. 



All five adult females have a parasitic Isopod in the marsupium, probably 

 a species of Prodajus, and allied to P. ostendensis Gilson which inhabits the 

 marsupium of the European Gastrosaccus spinifer Goes. 



EUCHAETOMERA G. O. Sars (1883). 



To this genus Brutomysis Chun and Mastigophthalmus Illig ought to be 

 referred. That Brutomysis must disappear is certain, as its single species, 

 B. vogtii Chun, is without doubt a synonym to E. tijpica G. 0. S. And Mastigoph- 

 thalmus does not show any difference from Euchaetomera of real generic value, 

 as the appendix at the eye-stalks is rather developed in E. typica, and the spinu- 

 lation, length of flagella, etc., are only specific characters. 



Three species, all captured in 1904-1905, are represented in the collection, 

 and one among them is new. 



19. Euchaetomera typica G. O. S.\r.s. 



Plate 2, figs. 5a-5c. 



1883. Euchaflomem typkn G. O. Sars, Forh. Vid. Sclsk. Christiania for 1SS3, no. 7, p. 42. 



1885. Euchaetomera lypicn G. O. Sars, Challongpr Rppt., 13, p. 211, pi. 37, figs. 1-20. 



1896. Brutomysis Vogtii ChuN, Bibl. Zool., 7, heft. 19, p. 179, taf. 1.5. 



1906. 1 Euchaetomera limhata Illig, Zool. Anz., 30, p. 203, fig. 10, A-D. 



Sta. 4734. Jan. 22, 1905. Lat. 17° 36' S., long. 122° 35.6' W. 300 fms. to surfaop. 2 specimens. 



As the two specimens, a female with marsupium and an immature female 

 (together with a third specimen from the Atlantic) differ considerably in a 



