HAWAIIAN ACANTHURID CALIGOIDS — LEWIS 237 



Fourth thoracic leg ovoid, much smaller than preceding thoracic 

 legs. Shape of appendage variable (figs. 247i-2>) ; median groove pres- 

 ent, extending into leg about one-fourth greatest length of appendage. 



Caudal rami minute, projecting slightly from ventral surface of 

 caudal projections of abdomen. Separated from abdomen by incom- 

 plete groove; two additional, incomplete transverse grooves in distal 

 half of appendage. Caudal rami with six naked setae, three from 

 apex, three from posterior lateral margin (fig. 24g). 



Remarks.^ — ^Nordmann's description of P. calamus (1864) was made 

 from a series of specimens. Since the original description, specimens 

 of this species, including the type specimens, have not been examined. 

 Although the length of the presently described specimens is con- 

 siderably less than the 5 mm. noted by Nordmann for the type speci- 

 mens, the specimens are placed tentatively in the species because of 

 the general characteristics that they possess in common with those 

 originally described by Nordmann for P. calamus. 



Specimens of P. calamus? collected by the author are similar to P. 

 minuticaudae Shiino in the general shape of the body, the makeup 

 of the thoracic leg-bearing segments, the cephalic appendages, and 

 the thoracic legs. The author is indebted to Dr. S. M. vShiino for 

 comparing specimens of the Hawaiian species with his specimens of 

 P. minuticaudae. According to Shiino (in correspondence), the Ha- 

 waiian specimens possess ''a longer abdominal process which extends 

 straight backward and is more deeply and more distinctly bilobed 

 forming somewhat divergent lobes." In P. minuticaudae "the proc- 

 ess is shorter, more shallowly bilobed and never extends straight back- 

 ward, but remams to form a mere triangular stump in lateral view." 

 These characteristics, in addition to others indicated by Shiino (in 

 correspondence), suggest that, although the two species possess sim- 

 ilar morphological characteristics, they are distinct. 



References 

 Baird, W. 



1850. The natural history of the British Entomostraca. Ray Soc, London, 



vii + 364: pp., 36 pis. 

 Bassett-Smith, p. W. 



1896a. A list of the parasitic Copepoda of fish obtained at Plymouth. Journ. 



Mar. Biol. Assoc. United Kingdom, vol. 4, no. 2, pp. 155-163. 

 1896b. Parasitic Copepoda of fish obtained at Plymouth. Ann. Mag. Nat. 



Hist., ser. 6, vol. 18, pp. 8-16, pis. 3-6. 

 1898a. Some new parasitic copepods found on fish at Bombay. Ann. Mag. 



Nat. Hist., ser. 7, vol. 1, pp. 1-17, pis. 1-7. 

 1898b. Further new parasitic copepods from fish in tlie Indo-Tropical Region. 



Ann. Mag. Nat. Hist., ser. 7, vol. 2, pp. 77-98, pis. 3-6. 

 1898c. Parasitic copepods from fish in the Indo-Tropical Region. Ann. Mag. 



Nat. Hist., ser. 7, vol. 2, pp. 357-372, pis. 10-12. 



