456 Transactions of the Society. 



(Ecistes cristatus sp. n. Plate XIX, fig. 5. 



Specific Characters.^ — Large and stout. Corona much wider 

 than trunk, bearing towards the ventral edge a small pectinate 

 process, and towards the dorsal edge two very large hyaline 

 processes, which curve forward. Anus nearly on a level with chin. 

 Toot wrinkled. 



Bescrijjtion. — Length (with foot partly contracted) 320 /jl, trunk 

 120 /JL, foot 100 fjL ; breadth of head (dorso-ventral) 145 /x, of trunk 



The animal is closely related to CE. pectinifer Murray (12),. 

 with which alone it is necessary to compare it. The process on 

 the corona, shaped like a hand, is in this species smaller and less 

 deeply lobed. The other two processes are much larger and 

 expanded into hyaline ridges, which in lateral view recall the crest 

 of the bird known as '' cock-of-the-rock," hence the specific name. 

 The chin is less prominent and bears no processes. 



The lack of further detail and of figures of the animal in other 

 positions is due to an accident which destroyed the preserved 

 specimen. The cover slip got cracked and it dried up. 



Habitat. — Pond in Sydney. 



Monommata appendiculata Sten. {H). 



While agreeing entirely as to general form with Stenroos's 

 animal, there are several points of difference, which, while they 

 may not be of specific value, yet should be noticed. 



The pointed dorsal process on the foot is, in my examples, 



EXPLANATION OF PLATE XIX. 



Fig. 1. — Monostyla lamellata. Dorsal view. 

 ,, 2a. — M. hatillifer sp. n. Dorsal view. 

 ,, 26. Ditto. Ventral view. 



„ 2c. Ditto. Toe. 



,, 3a. — Monostyla sp. Dorsal view. 

 ,, 36. Ditto. Toe. 



,, 4rt. — Pterodina striata ^^.n. Dorsal view. 

 ,, 46. Ditto. Anterior part (ventral). 



,, 4c. Ditto. Optical section. 



,, 4cZ. Ditto. Part of the surface markings. 



,, 5. — CEcistes cristatus sp. n. 

 „ 6a. — Metoindia heterosty la s'p.n. Lateral view. 

 ,, 66. Ditto. Dorsal view. 



1, 6c. Ditto. Optical section. 



,, 7. — M. rJiomboidula- Dorsal view. 

 ,, 8. — M. ehrcnhergi. Dorsal view. 

 ,, 9. — M. quinq2iecostata. Dorsal view. 

 ,, 10a. Rattulus orca sp. n. Fully extended. 

 ,, 106. Ditto. Contracted. 



(All figures multiplied 270 diam.) 



