KOFOID AND SWEZY: UNARMORED DINOPLAGELLATA 485 



The species was next discovered by Colliu (1912), who recorded the dis- 

 covery of another individual in tlie student laboratory at Cette; also Faure- 

 Fremiet (1914) stated that Chatton had seen one at Banyuls-sur Mer, in the 

 JNlediterranean. Thus up to the time of Faure-Fremiet's discovery of his 

 "vingtaine" of individuals at Croisic on the west coast of France only six indi- 

 viduals had ever been recorded, and observations on these had been restricted 

 because of the rapidity of cytolysis. 



TJnfoi'tunately the misimderstandiugs which in the past had accunudated 

 about Erythropsis were not dissipated hj Faure-Fremiet's more a])undant 

 material. He regards his species as identical with Hertwig's E. agilis. It has, 

 however, a brown instead of a red pigment mass, albeit with a prominent red 

 core. Its proportions and structure, especially the ocellus, are so similar to 

 those of Erythropsis figured by Pavillard (1905) from Cette that we regard it 

 as E. paviUardi nom. sp. nov, and not E. agilis Hertwig. 



In three other verv important particulars Faure-Fremiet (1914) brought 

 confusion with regard to this slightly known organism. In the first place, he 

 oriented it with the epicone posterior and the prod anterior, thus reversing the 

 pi'evious orientation. He also described and figured the transverse fiagellum" 

 as arising in the distal end of the girdle from the attachment area, and running 

 around the body in the reverse of the direction universal in the Dinoflagellata. 

 Ijastly he figures the longitudinal fiagellum as emerging anteriorly from the 

 epicone. AYe have elsewhere (sec Kofoid and Swezy, 1917) given the gromids 

 upon which these three conclusions should he rejected as wholly untenable. 



Species and Distribution 



The first record of any form now referable to Erythropsis was made by the 

 eminent Riissian biologist Metchnikoff, who puldished (1874) in his accoimt 

 (in Russian) of his "Riese nach ^Madeira" a brief account of a delicate and 

 evanescent infusorian from the collections of the tow net in the tropical Atlantic 

 off Madeira in 1872, but did not figure or name it. He later (1885) recognized 

 its similarity to Hertwig's Erythropsis agilis, but believed its affinities to be 

 with the Suctoria. 



This genus now includes ten species. The first of these is Erythropsis agilis, 

 the type species originally described by Hertwig (1884) from the vernal plank- 

 ton of the Mediterranean off Sorrento. E. cochlea and E. cornuta were figured 

 by Schiitt (1895) as Pouchetia cochlea and P. cornuta from the collections of 

 the Plankton Expedition, presumably from the tro]iical Atlantic or from the 

 Bay of Js'aples. These, as figured, lack the prod, but the ocellus and epicone 

 are typically those of Erythropsis. In 1905 Pavillard described and figured 

 a small species taken from tlie Mediterranean at Cette in October as E. agilis 

 Hertwig. This was about half tlie size of Hertwig's form with a girdle located 

 fartlier ])osteriorly, esi)ecially towards its distal end and with a black instead of 

 a red ])igment Ijody. Jn view of the sjjeciation recorded by us in this genus 

 and the significance of size, girdle, and })igiiient mass in specific distinctions 



