24 THE VICTORIAN NATURALIST. 



trophi have the form characteristic of the family, but are much 

 smaller, being -023 mm. across, as against 072 mm. for some of 

 L. socialis measured for comparison. The fulcrum is pointed at 

 its termination, and not swollen as in L. socialis. The arrangement 

 of the internal organs does not vary from the usual type, except 

 that the alimentary tract is not so sharply divided into intestine 

 and stomach as in other species of the genus. A mounted speci- 

 men showed the anus to be ciliated. Three round nucleated 

 bodies were noticed towards the dorsal surface, just below the 

 dorsal gap, which are shown in fig. 1, the two anterior ones being 

 smaller proportionately to the third than figured. Fig. 1 was 

 drawn from a preserved specimen, figs. 2 and 3 from life. I am 

 indebted to Mr. W. Stickland for the careful manner in which he 

 has engraved the figures. 



I sum up the specific characters as follows : — Clusters fixed, 

 with a dense matrix of adherent tubes of a dirty brown colour. 

 Body of individual narrow and much elongated, terminating in 

 slender peduncles two-thirds of whole length. Corona rather 

 wider than body, slightly oval, with short axis, dorso-ventral, at 

 right angles to trunk, ciliate between wreaths. Dorsal gap 

 distinct. Antennas two, dorsal, minute. Dimensions. — Clusters, 

 up to 2.5 mm. diameter; individuals, .8 mm. to 1 mm. long; 

 corona, .08 mm. wide; body, .06 mm. ; trophi, .023 mm. across ; 

 ova, .07 by .048. 



Habitat — Heidelberg, Victoria. 



INTERMEDIATE HOSTS OF FLUKE.— Third Note. 



By Rev. W. Fielder. 



{Read he/ore the Field Naturalists' Club of Victoria, 10th Hay, 1896.) 



Some twelve snails have already been recorded for Victoria as 

 harbouring fluke embryos. One or two others from New South 

 Wales have since given examples, notably Isidora (Bulinus) 

 newcombi, together with varieties of Limnea brazieri, embryos 

 from these forms being more common now than earlier in the year. 

 Perhaps the most interesting find of the month, however, is that 

 of the occurrence of curiously modified fluke embryos in the Fresh- 

 water Mussel (Unio Australis). The cercaria embryos are some- 

 what oval in shape, the head region being narrower than the tail 

 region. Towards the posterior border a pinching-in takes place, 

 a segment, so to speak, being almost separated from the body 

 proper. From the groove thus formed springs a whip-like 

 structure on either side, each process when in a contracted condi- 

 tion being about the length of the body. The method of extend- 

 ing these processes is extremely interesting. The substance 

 appears to run out from the base like the tape from a winding 

 measure till it reaches a length five or six times that of the body. 



