THE MYXOSPORIDIA OP THE BEAUFORT REGION. 233 



Habitat. — Both disporous and polysporous forms abundant in the urinary bladder and ureters of 

 Cynoscion regalis. Every one of a large number of fishes examined was found to be infected. In some 

 individuals the polysporous forms were relatively rare, in others they were equally if not more abundant 

 than the disporotis. 



Remarks. — For a detailed account of the structure and development of this species the reader is 

 referred to a previous paper by the writer. (See Davis, 1916.) 



V Sinuolinea capsularis, n. sp. (PI. xxu, fig. loi, 102; pi. xxni, fig. 103-107.) 



Trophozoites. — Vegetative trophozoites colorless or light yellow, rounded to very irregular in 

 shape (fig. 101-103). Progressing by slow amoeboid movements. Wlicn first removed from the host 

 are usually rounded, but after being placed on the slide soon become very irregular in shape, due to 

 the formation of numerous large branched or arborescent pseudopodia formed entirely of ectoplasm 

 Ectoplasm transparent, usually distinctly granular (sometimes homogeneous in younger trophozoites), 

 merging gradually with the endoplasm. Often in rounded trophozoites no distinct ectoplasmic layer 

 can be made out (fig. 102). Endoplasm differs from ectoplasm chiefly in the presence of large numbers 

 of fat globules. In large trophozoites the endoplasm often contains one to several relatively large, 

 rounded bodies which are sharply differentiated from the surrounding protoplasm (fig. 102, 103). 

 These bodies are in all probability gemmules similar to those formed by S. dimorpha. • They are more 

 finely granular and more transparent than the surrounding protoplasm and are practically identical 

 with the small, free trophozoites shown in figure 104, which are very abundant. Trophozoites con- 

 taining several gemmules are usually rounded and motionless and appear to be more or less degenerate. 

 Many such trophozoites were observed to disintegrate, thus liberating the gemmules. Whether the gem- 

 mules in this species are only liberated through the disintegration of the mother trophozoite was not 

 decided. Sporulating trophozoites were rare and were never seen to contain gemmules. 



Diameter of rounded vegetative trophozoites up to 4om. 



Disporous; possibly also polysporous. No sporulating trophozoites with more than two spores 

 were observed, but many vegetative trophozoites were considerably larger than those containing spores, 

 the latter measuring only about 2-jn in diameter. 



Spore. — Approximately spherical, sometimes slightly elongated along longitudinal axis (fig. 105-107). 

 Sutural plane much twisted on its axis; sutural line forming a prominent ridge around spore. Cap- 

 sules and capsulogenous cells large and conspicuous, occupying more than one-half cavity of sporcyst. 

 Coiled filaments distinct. Sporoplasm distinct, granular, with numerous small fat globules. As is 

 often the case in this genus, the spores are easily distorted by mechanical and osmotic pressure, and 

 may then appear quite different from the normal form. 



Diameter of spore I2-I4f(, diameter of capsules 4.5M, length of filament 50M. 



Habitat. — Common in the urinary bladder of Paralichthys albiguttus. Also fotmd in the urinary 

 bladder of Paralichthys dentatus and Spheroides maculatus. In all cases the vegetative trophozoites 

 were abundant. Only a few sporulating trophozoites and free spores were observed and in most instances 

 were entirely absent. Nine individuals of P. albiguttus were examined diu"ing July and August, of 

 which eight were infected with this species, but in only one of the eight were sporulating trophozoites 

 and spores found, and then only in. small numbers. Most of the larger trophozoites contained gem, 

 mules, and apparently this is the common method of reproduction at this season. 

 "* Stnuolinea arborescens, n. sp. (PI. xxin, fig. 108-110.) 



Trophozoite. — Vegetative trophozoites colorless to light yellow; rounded to very irregular in shape; 

 actively amoeboid, forming large arborescent pseudopodia of ectoplasm (fig. 108). Ectoplasm well 

 developed, very distinct, hyaline, homogeneous. Endoplasm coarsely granular, sometimes containing 

 a few fat globules; several denser sporoblast cells can usually be distinguished. Older trophozoites 

 are less active and the ectoplasm is less distinct. In sporulating trophozoites the ectoplasm may 

 entirely disappear, the entire trophozoite consisting of a coarsely granular mass. 



Diameter of rounded sporulating trophozoites about 75^. 



Polysporous. 



Spore. — Rounded, slightly elongated along longitudinal axis (fig. 109, no). Capsules large and 

 conspicuous, opening a short distance apart on the capsular side. Sutural line forming a prominent 

 ridge, which makes a characteristic S-shaped turn on the capsular side (fig. no). Coiled filaments 

 very distinct. 



Length of spore ism, width 12/j, diameter capsules, 5^1. 



Habitat. — Common in the urinary bladder of Siphostoma floridcs. 



