THE COPEPOD GENUS PARANTHESSIUS — ILLG 393 



strongly characterized natural tendency of the group but, rather, 

 cuts across a well-discernible trend. Consideration of species of 

 Anthessius Delia Valle (s^'nonym: Pseudomolgus Sars, Wilson, etc.) 

 as typical lichomolgids has perhaps contributed to this viewpoint. 

 I suggest that a more significant subdivision would set aside Anthes- 

 sius, Rhinomolgus Sars, perhaps Panaietis Stebbing, and other genera, 

 as well distinguished froim the Lichomolgidae proper, either as a 

 family or subfamily. The forms retained in the Lichorrbolffus-\m& 

 follow, without necessity of subdivision, several trends which may or 

 may not be of generic value but are hardly of familial or subfamilial 

 importance. Such trends all seem to have strong foreshadowing in 

 the genus Par anthessius. A conspicuous example would be the series 

 exhibiting suppression of the fourth endopodite, as discussed above. 

 Again, a series may be selected in which is traced the progressive 

 transfer of tlie prehensile function from the terminal podomere of 

 the antenna to the j^enultimate segment. Suggestions of various 

 trends of modification of the rostrum are apparent. Such species 

 as P. saxidoTYiae, P. j'ohustus^ and P. serendibicus perhaps anticipate 

 the great circular expansion in outline of the anterior body region, 

 seen characteristically in the Stellicola section of Lichomolgus. P. 

 columhiae, particularly in the adult female, shows the tendency of 

 elongation and narrowing of the body in the direction of vermiform 

 construction found in some of the most aberrant of the parasitic 

 copepods. This trend is further suggestive of significance when it 

 is noted than an accompanying phenomenon is the extension of the 

 ovarian (or oviducal?) structure out into the full extent of the 

 abdomen. 



Family LICHOMOLGIDAE Claus 



Genus PARANTHESSIUS Claus 



Paranthessius Claus, 1889, pp. 342-343 (type, P. anemoniae Claus, 1889).— Canu, 

 1891, p. 479 ; 1892, p. 236 ; 1894, p. 137 ; 1898, pp. 413^15.— Zulueta, 1912, 

 p. 12.— MoNOD and Dollfus, 1932, pp. 143-146.— Wilson, 1932, p. 587.— At- 

 kins, 1934, p. 674.— Leigh-Sharpe, 1935, pp. 47-48.— Nicholls, 1944, p. 53. 

 (Not Paranthessius T. Scott, 1903, p. 130.) 



Diogenidiuni Edwakds, 1891, pp. 89, 93 (type, D. nasutum Edwards, 1891 ) .— Canxj, 

 1891, p. 479 ; 1892, p. 236.— Wilson, 1932, p. 587. 



Herrmannella Canu, 1891, pp. 479-480 (type, H. rostrata Canu, 1891) ; 1892, pp. 

 235-236.— T. Scott, 1894, p. 259.— Canu, 1899, p. 73.— Norman and Scott, 

 1905, p. 299.— T. Scott, 1906, p. 354 (part).- Pelseneek, 1929, pp. 35, 43.— 

 Fbaser, 19.32, p. 279. 



Hermamiella Canu, 1891, p. 436; 1894, pp. 3, 10.— Thompson and Scott, 1903, 

 pp. 282-283 (part).— Norman and Scott, 1906, p. 199 (part).— Sars, 1918, 

 pp. 174-175 (part).— Brian, 1924, p. 5.— Wilson, 1932, p. 586.— Heegaard. 

 1944, pp. 361, 365. 



Herrmanella T. Scott, 1903, p. 28. — Pexseneer. 1929, p. 45. 



