BY T. HARVEY JOHNSTON AND O. W. TIEGS. 125 



to determine their systematic position. Monticelli's subfamily name, Acanthocoty- 

 limae may be retained at present. Meanwhile, the following suggestions may be 

 made: — 



It seems certain that ^1. verrilU Goto and A. lobiancM Montic. are Gyrodacty- 

 loidea, allied, perhaps, to the Gyrodactylinae. The presence of an accessory 

 armed disc in A. verriUi is suggestive of what occurs in the Lepidotreminae, but 

 there is probably no real relationship. The follicular nature of the testis shows 

 Microcotylid afiSnities, a view which is streng-thened when we consider that in this 

 genus Acanthocotyle we have a transition between head-organs and the oral 

 suckers of that group. This view is rendered more probable when we remember 

 that in Empleurodiscus the head-organs are actually protrusible and may there- 

 fore have some secondary attaching function. 



Appendix to Acanthocotylinae. 



35. LoPHOCOTYLE Braun, 1896. 



Body flat, tongue-shaped, with distinctly marked off head region, at the 

 front of which two gToups of unicellular glands open. Disc large, circular, pro- 

 vided with numerous large radial ridges, and a ring of booklets marginally. In- 

 testine bifurcate, provided with caeca. Genital pore close behind pharynx just 

 to left of midline. Testes numerous; vas deferens with large convoluted vesicula; 

 cirrus with straight spicule. Ovai-y oval, in front of testis. Vagina ?. Eggs 

 provided with operculum and with basal filament. Parasites on body of marine 

 bony fish. 



Type and only known species, L. cyclopiwra Braun. 



From Notothenia sp., locality Puerto Toro (Hamburg Magellan-Expedition). 



This genus which, in its form and intestinal characters, reminds one of 

 Epibdella, is usually considered as a member of the Monocotylidae, but the pre- 

 sence of glandular head-organs will not admit of its inclusion in that group. 

 Monticelli (1903, p. 336; 1905, pp. 68-70) grouped it along with Dionchus, 

 Merizocotyle, Anoph discus and Lintonia * in his subfamily Amsocotylinae bu'b 

 the non-existence of a generic name corresponding with the subfamily designation 

 prevents the retention of Monticelli's name. Pratt (1900) placed it next to 

 Dionchus but the presence of numerous testes and intestinal caeca, as well as the 

 general structure, seem to us to prevent its inclusion in the Calceostomidae. The 

 testicular arrangement and general form of the worm remind one of Acanthocotyle 

 Montic, but the latter does not jDOSsess intestinal caeca. In the light of our 

 present knowledge we propose to attach the genus provisionally as an appendix 

 to the Acanthocotylinae. 



Subfamily 11. PROTOMICROCOTYLINAE, n. subfam. 



36. Protomicrocotyle, n.gen. 



(Syn. Acmithodiscus MacCallum, 1918, nee 1916; nee Uhlig, 1906.) 



An elongate minute form, with distinct disc clearly marked off and bearing 

 several hooks. Four small suckers towards the posterior end of the body. Pos- 



*Lintonia was proposed by Monticelli (1904) to receive Nitzschia papulosa Lin- 

 ton from Gadus callarias from Massachusetts. We have not been able to consult 

 MonticeUi's paper but Linton's figures and short account (1898) show that the 

 species cannot rightly be included under Nitzschia. The general form and the 

 character of the testes suggest that Lintonia belongs to the Gyrodactylidae but in 

 view of our lack of information regarding the "lateral suckers," as to whether they 

 are "bothria" or else glandular "head-organs," we are unable to state whether the 

 genus is to be regarded as a member of the Gyrodactyloidea or the Tristomoidea. 



