425] STUDIES ON MYXOSPORIDIA—KUDO 187 



13(10) Sutural line forming an acute angle with longitudinal axis of spore 14 



14(15) Shell thickened at extremities; polar capsules ovdidal; length 10 to \^ix, breadth 

 6 to 8/i, length of polar capsule 4/t 



Myxidium striatum Cunha et Fonseca 1917 (116) 



15(14) Shell uniformly thick; polar capsules rounded pyriform; length 10 to 12/k, breadth 

 6ix, length of polar capsule 3 to 4ai 



Myxidium macrocapsulare Auerbach 1910 (113) 



16( 1) Breadth of spore less than half of length 17 



17(34) Breadth more than one-third of length 18 



18(25) Shell-valves unstriated 19 



19(22) Extremities of spore pointed 20 



20(21) Spore: extremities sharply pointed; greatly curved; narrow; length 12 to 14pt, 

 breadth 5 . 5 to 6/x, thickness 2.5 to 3/x 



Myxidium depressum Parisi 1912 (114) 



21(20) Spore: extremities not so sharply pointed; not greatly curved; broader; length 

 16.2 to 19m, breadth 7 to 9/x 



Myxidium bergense Auerbach 1909 (112) 



22(19) Extremities of spore not pointed 23 



23(24) Spore larger; length 15 to 20^, breadth 7 to 8m 



Myxidium spltaericwn Thelohan 1895 (109) 



24(23) Spore smaller; length 6(?) to 14m, breadth 4 to 6fi. Trophozoite mictosporous 



Myxidium gadi Georgevitch 1916 (H^) 



25(18) Shell-valves striated 26 



26(33) Spore definite in shape 27 



27(28) Spoi-e constricted in middle part of length; length 15m 



Myxidium histophilum Thel0|han 1895 (109) 



28(27) Spore regularly fusiform 29 



29(30) Vegetative form produces cyst. Spore: length 12 to 15m, breadth 6m 



Myxidium barbaiulae Cepede 1906 (HO) 



30(29) Vegetative form does not produce cyst 31 



31(32) Sutural line slightly curved in S-form; length 15 to 16m, breadth and thickness 



5.5 to 6m 



Myxidium americanum Kudo 1919 (117) 



32(31) Sutural line not curved in S-shape, but bent to one side; length 15 to 18m, breadth 

 and thickness 6 to 7 m 



Myxidium kagayamai Kudo 1919 (117) 



33(26) Spore variable in form; straight and constricted; one side concave, the other con- 

 vex; arch-shaped, etc.; length 13 to 18m, breadth 5.2 to 5.8m 



Myxidium pfeifferi Auerbach 1908 (Ill) 



34(17) Breadth of spore equal to or less than one-third of length 35 



35(40) Shell-valves unstriated 36 



36(37) Spore greatly elongated (breadth: length = 1 :6 . 2) ; length 21 . 6 to 25 . 2m, breadth 



3.6 to 4m 



Myxidium proceriim Auerbach 1910 (112) 



37(36) Spore less elongated (breadth: length = 1 :3 or 1 :3 .4) 38 



38(39) Spore large; valves asymmetrical; length 28m, breadth 8m 



Myxidium giganteum Doiflein 1898 (HO) 



39(38) Spore small; valves symmetrical; length 12m, breadth 3 to 4m 



Myxidium danilewskyi Laveran 1897 (109) 



40(35) Shell-valves striated 41 



41(44) Spore definite in shape 42 



Numbers enclosed in parentheses refer to the page of the article on which is found the description of the species 

 named. 



