126 NEW GYEODACTYLOID TEEMATODES PROM AUSTRALIAN PISHES^ 



terior part of body-surface apparently developed into spiny papillae. No eyes. 

 Two mouth suckers present. Small pharynx. Numerous follicular testes and a 

 long narrow vas deferens. Penis armature in the form of a coronet of spines. 

 Single ovary. Apparently a single egg with a spine and a long filament. 



From the gills of a marine fish, Caranx hippos — New York Aquarium. 



Type and only known species, P. mirabilis (MacCallum, 1918), J. &. T. 



This remarkable worm was described by MacCallum (1918) under the name 

 Acanthodiscus mirabile, n.gen. et sp. As already pointed out the generic name 

 was already preoccupied and therefore not available for use. The name Proto- 

 microcotyle is therefore suggested and is intended to emphasize the systematic 

 relationship of the worm. 



The presence of a distinct disc and (apparently) of a single egg, suggests 

 Gyrodactyloid affinities. On the other hand, there are two mouth-suckers, a long 

 series of testes, a "cirrus-coronet," and suckers on the posterior portion of the 

 body, characters which distinguish the Microcotylidae. 



MacCallum suggested that the genus was a member of the Gyrodactylidae. 

 This is clearly incorrect, the entire absence of head-organs serving to exclude it 

 from that group. Nor is it a true Microcotylid. It seems more probable that 

 we have here an organism which is intermediate between the Gyrodactyloidea and 

 the Microcotylidae, with stronger affinities towards the latter group, and that a 

 more accurate study of its anatomy may lead to its falling into a new family. 

 For the present it may stand as the type of a new subfamily, Protomicrocotylinae, 

 whose characters, as far as is now known, would be those of the genus. 



List of Australian hosts and gill-parasites referred to in this paper. Freshwater 

 fish indicated by an asterisk. 



Family Dasyatidae (Stingrays). 



Vrolophus testaceus MuUer & Henle Monocotyle robiista J. &. T. 



Family Plotosidae (Eel catfishes.) 



* Tandanus tandanus Mitchell. Anchylodiscus tandani J. and T. 



* Neosilurus hyrtlii Steind. Anchylodiscus sp. 



Family Serranidae (Perches). 



* Therapon carbo Ogilby and McCuUoch. Protogyrodactylus quadratus J. and T. 



Daitreosoma constrictum J. and T. 

 Lepidotrema therapon J. and T. 



* Therapon fidiginosus Macleay. TrivitelUna subrotimda J. and T. 



Lepidotrema fiiliginosiim J. and T. 

 Flabellodiscus simplex J. and T. 



* Therapon hilli Castln. Daitreosoma bancrofti J. and T. 



Lepidotrema tenue J. and T. 



* Therapon unicolor Gunther. Empleurosoma pyriforme J. and T. 



Empleurodiscus angustus 3. and T. 

 "PlectropUtes ambiguus Richdsn. Lepidotes fhtviatilis J. and T. 



Family Sparidae (Sea breams). 

 Girella tricitspidata Q. and G. Acleotrema girellae J. and T. 



Sparus australis Gunther. Lam-ellodiscios typicus J. and T. 



Family MuUidae (Red Mullets). 

 TJpenaem signatiis Gunther. Haliotrema australe 3. and T. 



Family Sciaenidae (Jew fishes). 

 Sciaena antarctica Castln. Calceostoma glandidosum 3. and T. 



