520 ORDER HOLOTRICHA. 



extremity being slightly narrower than the shoulder portion of the bottle-shaped 

 body, while the projecting neck is more attenuate. Colour bright green. Length 

 1-288". 



Genus IV. MARYNA, Gruber. 



Animalcules ovate or cup-shaped, with an anterior projecting funnel- 

 shaped neck, which is cleft on its ventral aspect and fringed along its 

 anterior edge with a single row of long cilia ; finer vibratile cilia distri- 

 buted over the whole cuticular surface ; oral aperture situated at the base of 

 the anterior cleft, followed by a fissure-like pharj-ngeal passage. Habits 

 social, secreting and inhabiting a common tubular zoothecium, to the walls 

 of which they are not permanently united. 



Marsma socialis, Griiber. Pl. XXXII. Figs, ii and 12. 



Zoothecium dichotomously branched, granular and finely striate trans- 

 versely, narrower or constricted at the commencement of each bifurcation ; 

 colour light brown or yellowish ; contained zooids projecting slightly from 

 their respective thecae ; cup-shaped, one and a half times as long as broad ; 

 the posterior border rounded, the anterior one truncate, with a centrally 

 developed, ventrally cleft, funnel-like neck, a cleft on the ventral aspect of 

 the anterior border corresponding with that in the neck; pharynx continued 

 backwards to within a short distance of the posterior border; ante- 

 rior wreath of cilia very long and fine ; contractile vesicle situated near the 

 termination of the ventral cleft ; endoplast unobserved. Length 1-165". 



Hab. — Salt water. 



The position of this animalcule is ob\'iously near Lacrymaria and Phialina, 

 from both of which it most conspicuously differs in its social habits and construction 

 of a common zoothecium. A translation of the original description of this species, as 

 figured and described by Dr. Gruber,* in common with various other interesting 

 infusorial forms, is given in the ' Journal of the Royal Microscopical Society ' for April 

 1880. A closely corresponding branching zoothecium is constructed by the Hypo- 

 trichous type Stichotricha socialis, described by Dr. Gruber in the same serial. 



Genus V. LAGYNUS, Quennerstedt. 



Animalcules free-swimming, elastic, more or less flask-shaped ; oral 

 aperture terminal, followed by a longitudinally plicate tubular pharynx ; 

 a circle of longer cilia surrounding the oral aperture, but not, as in Tra- 

 cJidocerca and Lacrymaria, set in a distinct annular groove or furrow ; 

 general cuticular surface entirely ciliate ; contractile vesicle and endoplast 

 conspicuous. 



Quennerstedt t has adopted as the tj-pe of this genus the Lacrymaria elegans of 

 Engelmann,J adding to it a second species observed by himself. The pecuhar 

 structure of the pharyngeal tube, which approximates that of Trathelophylluin and 



* ' Zeitschrift fiir Wissenschaftliche Zoologie,' Bd. xxxv., 1S79. 



t ' Sveriges Infusoriefaima,' 1S67. 



j " Zur Naturgeschichte der Infusionsthiere," ' Zeit. Wiss. Zool.,' Bd. xi., 1862. 



