4 Prof. R. Kossmann on the Cryptoniscida3. 



has been already gratefully mentioned, Ci-yptoniscus paguri 

 at Malion, in the island of Minorca ; at other opportunities I 

 have also examined single specimens of nearly all the forms 

 pertaining here. Upon these investigations the following 

 brief expositions are founded. 



But before I enter upon the actual subject, a formal neces- 

 sity presses itself upon me. As in my monograph I must, of 

 course^ employ a critically sifted and correctly established 

 nomenclature, and yet must not lay too great difficulties in 

 the way between the preliminary and the detailed work, I 

 think I ought here to give a small table relating to this 

 matter. 



I. Parasites on Cirripedes. 



a. Upon non-parasitic Cirripedes {Balanus balanoides and Creusid). 



1. Cryptotiiir, Dana, 185:3 (U. S. Expl. Exped., Crustacea, p. 801). 

 Synonymy: — Hemionisctis, Buchbolz, 1806. 



Cryptothiria (p. parte), Spence Bate & Westwood, 1868. 



b. Upon parasitic Cirripedes. 



a. Free in the mantle-cavity. 



2. EuMETOR, Kossmann, 1872 (^Beitr. z. Anat. d. sclimar. Rankenfussler, 



Anhangj. 



/3. Perforating the mantle from within. 



3. LrRiopsis, Max Schultze, 1859 ('' Anm. zu einer Aufsatz von Fritz 



Miiller," in Wiegmann's Archiv, Bd. xxv. p. 310). 

 Synonymy: — Lirinpe, llathke, 18-13, nom. prseocciip. (Lesson, 1837, 

 Trachy medusffi) . 

 (This form is referred by F. Miiller and Fraisse to O'yp- 

 toniscus, by Spence Bate to Cryptothiria). 



y. Attacking the peduncle from without, and displacing the cirri- 

 pede down to the roots. 

 aa. Upon Peltogaster, with short cephalon. 



4. Cryptoniscus, Fritz INIiiller, 1870 (Jena. Zeitschr. Bd. vi. p. 01). 



/3^. Upon Sareulina, with long cephalon penetrating deeply into 

 the Brachyuran. 



5. Zeuxo, Kossmann, 1872 (Beitrage z. Anat. d. schm. Rankenf.), nom. 



prseoccup. by Templeton, but suppressed by Dana in favour of Tanms. 



II. Parasitic on Ostracoda. 



0. Cyproniscus, Kossmann, gen. nov. Referred by Sars (" Oversigt af 

 Norges Crustaceer," in Christ. Vidensk. Selsk. Forhaudl. 1882, 

 no. 18, p. 73) to Cryptothiria. 



"III. Parasitic on Isopoda. 



7. Cabirops, Kossmann, gen. nov. 



Synonym : — Cahira, Kossmann, 1872 (Beitrage &c., Anhang), nom. 

 preeoccup. (Treitschke, 1825 Cahera, Jodoffjsky, 1837 

 Cabira, Lepidoptera). 

 Referred by Sars (Oversigt &c. p. 74) to Cryptothiria. 



