482 ME. p. w. BASSEiT-SMiTH ON [Apr. 18, 



tinetly segmented. Genital ring short. Abdomen small, with two 

 minute caudal plates. Posterior autennse strongly uncinate. All 

 four pairs of thoracic limhs present, biramose and triarticulate. 



(1) Theeodamus seeeani, 5 . 



Therodamus serrani Kr. Bidrag til Kundskab, 1863, p. 316, 

 pi. XV. fig. 4. 



Host : gills of Serramis sp. West Indies. 



Gr. 3. Pei^iculus Nordm. 



Head oval, without horn-like processes. Thorax distinctly seg- 

 mented, giving rise to four pairs of limbs, the first two pairs being 

 placed close behind the head, the third and fourth some distance 

 removed from them and from each other. Genital segment very 

 long. Abdomen small, with minute caudal plates. 



Male smaller than female, with a short genital segment. 



(1) Penioulus fistula. $ S . 



Peniculus fistula Nordm. Mikrog. Beitrage, 1832, p. 107, pi. vi. 

 fig. 8. 

 „ M.-E. Hist. Nat. Crust, iii. 1840, p. 497. 

 „ „ Heller, Eeise d. Novara, 1865, p. 248, pi. xxv. 



fig. 3. 

 „ „ Claus, Eech. liber Lemceocera &c. 1868, p. 12, 



pis. ii., iii 

 Host : Zeus faber. 



(2) Peniculus fuecatus. $ . 



Peniculus furcatus Kr. Bidrag til Kundskab, 1863, p. 268, 

 pi. xii. fig. 4. 

 „ „ Claus, op. cit. 1868, p. 12. 



Host : gills of Holacanihus [Tetrodon] sp. East Indies. 



, (3) Peniculus clatatus. $ . 



Peniculus clavatus Kr. Bidrag til Kundskab, 1863, p. 266, pi. xiv. 

 fig. 8. 



Lerncea clavata Miill. 



Host : fins of Sebastes norvegicus. Greenland. 



G. 4. Penella Oken. (Lemceopinna Blainv.) 



Head large, globose, tuberculate, with arm-like projections directed 

 backwards ; the neck is long and straight, not distinctly segmented, 

 united with the elongated genital segment in the same hne. 

 Abdomen penniform. Pour pairs of Hmbs are present, placed close 

 behind the head and together ; the first two are biramose, the third 

 and fourth uniramose, eacli branch with t\A o joints. 



Male minute, not elongated. 



Young form of female as " Hessella cylindrica " Brady, Chall. Eep. 

 vol. xxiii. p. 190, pi. xxix. figs. 40-42, and Bacillus elongatus, 



