670 ON CRUSTACEA BROUGHT BY DR WILLEY FROM THE SOUTH SEAS. 



shell where the nuchal region of the animal plays upon the shell." In his ' Letters 

 from New Guinea,' Quart. Journ. Micro. Sci., vol. 39, p. 14-5, 1896, he wrote as 

 follows : — " Ectoparasites. In my previous note [Natural Science, vol. (5, June, 1895] 

 I accidentally omitted to mention the occurrence of numerous Copepod parasites in the 

 mantle-chamber of the Nautilus. They are present in nearly every individual that I have 

 examined, and are found attached to the branchiae, the internal surface of the funnel, 

 and in other regions of the pallial chamber. The parasites are a species of the genus 

 Caligus and possess the characteristic semi-lunar suckers on the first pair of antennae. 

 When Nautili are placed in jars the Caligids emerge in large numbers from the 

 mantle-chamber, and swim about actively in the water, usually in close proximity to 

 the sides of the vessels, ft-om which they can be removed only with some difficulty, 

 owing to the great adhering power of the above-mentioned suckers." A foot-note 

 gave the name C. nautili, pending a more detailed description. It well deserves to be 

 retained. 



Gen. Gloiopotes, Steenstrup and Llitken. 



1861. Gloiopotes, Steenstrup and Llitken, K. Danske A'id. Selsk. Skr., Scr. 5, vol. 5, 

 p. 36.3 (23). 



1868. Gloiopotes, Heller, Crustaceen der Novara, p. 161. 



1889. Lepeophtheirus, G. M. Thomson, Trans. N. Zealand Inst., vol. 22, p. 3.54. 



1889. Gloiopotes, Bassett-Smith, Proc. Zool. Soc. London, p. 458. 



Bassett-Smith gives the definition in the following form : — " Carapace large, oval, 

 scutiform. No lunulas on the frontal border. Fourth thoracic segment with two dorsal 

 plates partly covering the genital segment, the latter being produced backwards by two 

 elongated curved processes having a styliform appendage projecting from the outer border, 

 serrated at the edge. Abdomen long. Caudal plates lanciform. Firsfr and fourth thoracic 

 limbs single-branched, second and third double." 



Of the two species known, the type G. hygomianus has the two dorsal plates of 

 the fourth thoracic segment irregularly oblong and the stiliform appendages of the 

 genital segment not reaching the apices of the processes from which they project, 

 whereas in G. huttoni (Thomson) the dorsal plates are semi-lunate, and the stiliform 

 appendages project beyond the apices of the prolongations of the genital segment. 



The terminal caudal appendages might rather be called filiform than lanceolate ; 

 there is nothing leaf-like or laminar about them. The definition, as explained further 

 on, requires some modification now. that the male of the type species is known. 



Gloiopotes hygomianus, Steenstrup and Llitken. Plate LXXIV a. 



1861. Gloiopotes Hygumianiis, Steenstrup and Llitken, K. Danske Vid. Selsk. Skr., 

 Ser. 5, vol. 5, p. 363 (23), pi. 5, fig. 9. 



1899. Gloiopotes hygomianus, Bassett-Smith, Proc. Zool. Soc. London, p. 458. 



Only the female of this species was described by Steenstrup and Llitken. The 

 specimen was taken in the Atlantic from some unnamed fish. Dr Willey's specimens 



