Phylum Fungilli [217 



Subclass Gregarinida Biitschli op. cit. Inhalt (1882). 



Order Septata Lankester in Enc. Brit. ed. 9, 19: 853 (1885). 



Order Brachycystida, suborder Gregarinidae, and tribe Cephalina or Folycystina 

 Delage and Herouard Traite Zool. 1: 255, 256, 269 (1896). 



Order Gregarinida Labbe in Thierreich 5: 4 (1899). 



^uhordtr Eugregarinaria Doflein Protozoen 160 (1901). 



Order Gregarinoidca Minchin (1912). 



Suborder Gregarininea and tribe Gregarinoidae Poche in Arch. Prot. 30: 234 

 (1913). 



Subclass Gregarinida, order Eugregarinida, and suborder Cephalina Calkins Biol. 

 Prot. 422, 428 (1926). 

 The typical gregarines, the vegetative cells elongate and divided by more or less 

 definite constrictions into two (or, occasionally, more than two) parts; not repro- 

 ducing asexually. 



Typical gregarines occur chiefly in insects. The vegetative cell consists of an an- 

 terior portion (protomerite) serving for attachment and a posterior portion (deuto- 

 merite), containing the nucleus, lying in the gut cavity of the host. Both parts have 

 a thick outer layer, commonly differentiated upon the protomerite into a more or 

 less elaborate knob, the epimerite. Longitudinal fibrils, presumably contractile, are 

 present. The cells writhe actively. 



The individuals are commonly found in pairs, one member attached to the epi- 

 thelium of the gut, the other to the posterior end of the first. This arrangement is 

 produced by active self-placement on the part of the second member. When both are 

 mature, they take common action to produce a globular cyst. The protoplasts remain 

 distinct until both have become multinucleate, after which they produce numerous 

 gametes. In some forms, as Nina, studied by Goodrich (1938), all of the gametes 

 migrate from one cell, recognizably male, into the other, the female cell; the male 

 cell is left empty and is compressed or crushed by the growth of the zygotes in the 

 female cell. The zygotes are spores, usually fusiform, and usually producing sporo- 

 zoites by eights. In Gregarina and Gamocystis, an inner layer of the cyst wall is so 

 modelled as to form tubes (sporoducts) running from the surface to the interior. 

 When the spores are ripe, the sporoducts become extroverted and the spores are ex- 

 truded through them in uniseriate rows. In connection with this behavior, the spores 

 have flat ends like barrels. 



Family 1. Stenophorida [Stenophoridae] Crawley 1903. Protomerite a mere 

 knob. Stenophora. 



Family 2. Gregarinida [Gregarinidae] Greene 1859. Family Gregarinarien Stein 

 in Arch. Anat. Phys. 1948: 187 (1848). Gregarines which are without epimerites 

 and are not notably elongate. There are about a dozen genera. Cysts without sporo- 

 ducts: Hirmocystis, Hyalospora, Cnemidospora. Cysts with sporoducts, the spores 

 barrel-shaped: Gregarina, Gamocystis. The earliest observations of Sporozoa were by 

 Dufour ( 1826) , who, studying the anatomy of insects, found them in the gut of beetles. 

 He took them for worms and illustrated an individual with an epimerite, which he 

 took for a sucker. Later (1828) he applied names, Gregarina conica to the form first 

 seen, G. ovata to a form without an epimerite found in the forficule, i.e., in an ortho- 

 pteran. The former does not belong to the genus Gregarina as subsequently construed; 

 it appears to be a member of the family Actinocephalida. Gregarina ovata should be 

 regarded as the type of Gregarina, but the genus has usually been interpreted by G. 

 cuneata, which Stein observed in cockroaches. 



