22 RKSEARCHKS IN HELMINTHOLOGY AND PARASITOLOGY. 



Gregarina larvata. — Body opaque white, cylindrical or fusiform, 

 frequently considerably dilated at the middle of the upper third. 

 Superior cell a flattened or depressed sphere, received about one-half 

 into a depression of the inferior cell, surmounted by a papillary 

 elevation with traces of a communication with the exterior ; interior 

 filled with a finely granular mass resembling oil globules, and meas- 

 uring from i-i5oooth to i-7500th inch. lycngth of cell, in .smallest 

 individuals i-i23d inch; in largest i-8oth to i-6ist inch broad. In- 

 ferior cell elongated, cylindrical or fusiform, not communicating with 

 the exterior nor with the interior of the superior cell ; filled with a 

 mass of granules resembling that of the superior cell, rendering the 

 larger individuals opaque, but translucent in the smaller ones, and 

 usually obscuring one or two comparatively large nucleolo-nucleated 

 organic cells, measuring from i-88Sth to i -308th inch in diameter. 

 Cell-wall marked with exceedingly regular, delicate, longitudinal, 

 parallel lines about i -9375th inch apart, apparently muscular in 

 character. 



lycngth from i-i6oth to i-3oth inch by i-83oth to i-iiith inch 

 in breadth. 



Habitat. — Found in numbers from half a dozen to over a hundred, 

 in the ventriculus oi Jul its mar^inatics. 



Gregarina is probably the larva condition of some more perfect 

 animal, but in the 116 individuals of //^//« which I have examined, I 

 have not been able to detect any form which could be derivable from 

 it. Creplin doubts its animality.^ When I first discovered this 

 body, thinking it to be a larva, I did not examine it carefully, and 

 it was not until sometime afterwards when, being desirous of ascer- 

 taining its true nature, upon examining some fresh specimens be- 

 neath the microscope, / detected movements of an animal character, and 

 this led me to seek for muscular structure, zvhich resulted in the discovery 

 of the longitudinal lines of the inferior \ cell. These escaped the ob- 

 servation of Siebold, for he says, " Nach meine Beobachtungen 

 bestehen die Gregarinen aus einer harten glatten den Eihiillen der 

 Insekten-Eier ahnlichen Haut. ' ' % The movements of the animal are 

 exceedingly sluggish, and consist of a very slow bending in any 

 direction of an}^ part of the inferior cell, most usually above the 

 middle, rarely at the inferior extremity, but most frequently near 



* Nachtrage zu Gurlt's Verzeichness fer Thiere bei welchen Entozoen gefunden 

 worden sind. Wiegmann's Archiv, 1846, i Band, S 157. 



t Wiegmann's Archiv, 1838, 2 Band, S 308. 



JSee May, 1851. Dr. Leidy observed similar muscular structure (Proc. Acad. 

 Nat. Sci., No. 76, in Bibliographyj in the superior division. 



