Maskell. — On Freshwater Infusoria. 5 



the anterior end, where there is a smooth area. Contractile 

 vesicle single, sub-central. Flagellum single, as long as the 

 extended body. Colour white ; motion rather slow. 



Length ^jo inch = 29 it, extended. 



Hutt Valley, W. M. Maskell. 



The posterior tapering, smooth anterior area, and general 

 nail-shaped form distinguish this animalcule. 



Genus Oikomonas. 

 Oikomonas termo, James-Clark. Wellington. 



Genus Dendromonas. 

 Dendromonas producta, sp. nov. Plate I., fig. 2, a, b. 



Animalcules rounded posteriorly ; anterior border oblique, 

 slightly concave, produced at the angles to a point, which is 

 more or less visible according to the position of the animalcule 

 (fig. 2, b). Zoodendrium slender, translucent, erect, irregularly 

 branched but usually only dichotomous at the tip of the main 

 rachis. Flagella two, uneven in length. Contractile vesicle 

 single, sub-central. Endoplast posterior. 



Average total length of zoodendrium ^i^ inch = 90 it ; main 

 rachis usually longer than the branches. Length of zooids J^ 

 inch = 5-7 ix. 



Otaki, W. M. Maskell. 



The known species of this genus are all more or less pyri- 

 form, and show nothing of the oblique concave anterior edge 

 with produced angles of this species. 



Genus Cephalothamnium. 



Cephalothamnium coronatum, sp. nov. Plate I., fig. 3. 



Animalcules elongate-ovate, situated in a cluster at the 

 extremity of a long, slender, stiff, translucent pedicle : as many 

 as twenty sometimes in a cluster. Flagella two, unequal in 

 length. Near the bases of the flagella is a ring or coronet of 

 very minute granules, sometimes almost like spines. Contractile 

 vesicle single, sub-central. Endoplast not observed. 



Average length of pedicle, 3^ inch = 70 il ; length of zooids, 



2T00 inch = 10 i«- 



Hutt Valley, W. M. Maskell. 



The " coronet ' of gemmules clearly distinguishes this 

 species. 



Genus Stylobryon. 

 Stylobryon petiolatum, De Fromentel. Karori ; Otaki. 



Genus Goniomonas. 

 Goniomonas elongata, sp. nov. Plate I., fig. 4, a, b, c. 

 Animalcules free-swimming, elongate, sub-triangular or sub- 

 rectangular according to position, persistent in shape ; colour 



