20 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 121 



Hosts and distribution, — 8 host records: 



location hosts reference 



Hawaiian Islands Unknown Nordmann, 1864 



Acanthurus dussumieri Lewis, 1964a 



A. mata 

 A. olivaceus 



A. triostegus sandvicensis 

 Ctenochaetus strigosus 

 Naso hexacanihus 

 N. unicornis 



Material. — One ovigerous female collected by D. Watson from 

 the dorsal fin of Pervagor spilosoma (Lay and Bennett) from the 

 Honolulu Aquarium. 



Measurements. — Length from anterior end of head to posterior 

 end of abdomen, excluding projecting second antennae, 2.89mm. 

 Length of head 0.41mm; greatest width 0.28mm. Length of neck 

 0.22mm; greatest width 0.13mm. Greatest length of combined 

 fourth pedigerous segment, genital segment, and abdomen 2.15mm. 

 Length of egg strings 2.81 and 2.96mm. 



Description. — See Lewis, 1964a. 



Family Pennellidae 



Pennella Oken, 1816 



Diagnosis. — Female: Body heavily sclerotized, separable into 

 cephalothorax, neck, and trunk (including abdomen). Cephalothorax 

 suborbicular, consisting of cephalon and at least first thoracic segment; 

 oral region at or near anterior end, smTOunded by one or more types of 

 papillae. Two to thi'ee heavily sclerotized horns present on posterior 

 region of cephalothorax, at junction of cephalothorax and neck, or on 

 anterior end of neck; horns of variable length and shape, usually 

 projecting laterally or posterolaterally. Neck slender, cylindrical, 

 distinct from cephalothorax due to size difference, usually continuous 

 with trunk. Trunk elongate, cylmdrical or slightly flattened dor- 

 soventrally, with ventral indentation at genital openings and frequently 

 with annulations along entire length. Abdomen forming posterior part 

 of trunk, behind ventral indentation at genital openings, tapered 

 posteriorly; posterior sm'face bilobed due to anal indentation, bearing 

 minute caudal rami. Numerous branched or simple filiform processes 

 arising from lateral or ventral and ventral lateral surface of abdomen, 

 giving plumose appearance to posterior part of body. Egg strings 

 long, frequently more than twice the length of body. Antennule 2- to 5- 

 segmented, situated on dorsal surface of cephalothorax, behind an- 

 tennae. Antennae chelate, 2- or 3-segmented (movable portion of 

 claw designated as segment with terminal process). Mandibles of 



