23] STUDIES ON GREG ARI NES— RAM M 23 



possess an epimerite have the body behind it divided into protomerite and deutomerite by a 

 septum, and have hence been termed Polycystida . . . , while those without an epimerite 

 are also without a septum; hence Monocystida , . . But in one family, Doliocystidae, Labbfi, 

 an epimerite is present, and may attain a considerable size . . . without any septum dividing 

 the rest of the body ... It is purely a matter of definition whether those forms be con- 

 sidered as Cephalina without a septum, or as Monocystis with an epimerite. The Cephalina 

 in which the body is non-septate are sometimes distinguished as Dicystida from those in 

 which there is a distinct protomerite and deutomerite (Tricystida). These terms are to be 

 understood, however, in a purely descriptive sense, and cannot be used for classificatory 

 purposes, as there is no doubt that many dicystid species are derived from tricystid forms 

 secondarily, by obliteration of the protomerite .... On the other hand, such forms as the 

 Doliocystidae .... appear to be truly and primitively dicystid, and are to be regarded as 

 intermediate forms transitional from Acephalina to Cephalina. 



Genus LECUDINA Mingazzini 1891 : 469 

 Body non-septate, epimerite regularly simple. Spores ovoidal, thick- 

 ened at one pole. 



LECUDINA PELLUCIDA (Kolliker) Mingazzini Type species 



1848 Gregarina pellucida 



1851 Gregarina pellucida 



1859 Gregarina pellucida 



1872 Monocystis nereidis 



1891 Lecudina pellucida 



1893 Lecudina pellucida 



1893 Doliocystis pellucida 



1899 Doliocystis pellucida 



1903 Doliocystis pellucida 



1909 Doliocystis pellucida 



1913 Doliocystis pellucida 



Sporonts solitary, ellipsoidal or "bottle-shaped," rectangular or rounded 

 at anterior end and broadly rounded at posterior. Nucleus spherical. 

 Epimerite a simple small papilla. 



Cysts small, dehiscence by simple rupture, spores ovoidal, 7 by 5)ti, with 

 thickening at one pole. 



Taken at Triest, Naples, and in the Gulf of Marseilles. 



Intestine of Nereis cuUrifera Grube and N. beaucourdrayi Aud. Koi- 

 liker's figure indicates a differentiation in the protoplasm of the anterior 

 end of the body from that of the remainder. 



Mingazzini describes the body as nearly transparent, especially at the 

 anterior end, and both mentions and illustrates the retractility of the 

 anterior end within the body. 



