AN ATTKMPT TO REVISE THE FAMTLY (( LINGUATULIDAE » 



books for unlmowii terms with an antiquarian flavour. Still in tlie 

 interest of tlie science we must foUow some rules and tliat of 

 priority of nomenclature is one of the most important. This seems 

 to me a clear case, and much as we may regret the temporary 

 inconvenience, it seems to me right to try and restore Humboldt's 

 name for the genus. 



Leuckart characterizes the two gênera as follows : 



A. — LiNGUATULA Frohlich. 



Corpus depressum, dorso elevatum, marginibus crenatum. Camtas 

 corporis in latera annulorum porreeta, pectinata. 



B. — PoRocEPHALUs Humboldt {Pentastomum Rudolphi). 

 Corpus teretiusculum. Camtas corporis continua. 



1. — LiNGUATULA FUSILLA Dieslng (1). 

 Synonyms. — Pentastomum pusillum'Diesmg . 



DiAGNOsis. — « Corpus oblongum retrorsum attenuatum, ventre 

 planiusculo subelliptico , dorso con- 

 vexiusculo, supra et subtus versus mar- 

 gines manifeste transverse plicatum , 

 marginibus crenulatum. Caput trunca- 

 tum. Os orbiculare inter costas duas 

 oblique verticales retrorsum convergen- 

 tes et bothria arcuatim disposita, hamu- 

 lis simplicibus instructa, situm. Longit. 

 ad 1 1/2 '" latit. ad 3/4 '")). ~ Diesing. 



Habitat. — This form was found by 

 Natterer in the intestine of a female 

 Acara coscudo (?), amongst the food. This 

 fish is a member of the family Chro- 

 midae. 



This, if the spécimens figured by 

 Diesing were adult, is by far the smal- 

 lest of the hitherto described species. As 



(1) Denkschr. Ak. Wiss. TFito , XII, I.SijG, p.lJI. 



Fig. 1. — Liit{/uatiil(ijni,^illa 

 Diesing X ^^1- Altor Dic- 

 sina:. 



