OftO 



RECORDS OF THE AUSTRALIAN MUSEUM. 



collected some about fifty miles east of Sydney ; in 1907 Mr. J. 

 H. Close secured a fair number of small forms in Port 

 Jackson, and last year (1908) Mr. S. J. Johnston secured 

 some more, also in Sydney Harbour. Besides Sagitta serroden- 

 tata, Krohn, several other species are represented in the above 

 collections, all of which have been handed over to me. 



Fowler 9 and Michael 10 state that the best preservative for 

 these delicate organisms is weak formalin ; spirit producing 

 considerable distortion and the disappearance of the corona 

 ciliata. Whitelegge's specimens were preserved in alcohol, hence 

 the contracted state of the worms. 



Many writers have mentioned the fact that insufficient descrip- 

 tions have led to the establishment of many doubtful species. 

 The limits of variation in this group being very considerable, the 

 examination of a large number of specimens is necessary to firm]}' 

 establish and accurately define a species. There were only a 

 dozen at my disposal, all already mounted, and consequently I 

 am giving as complete a description as possible, leaving authorities 

 on this group to decide the validity of the proposed new species. 



The main results are tabulated along lines similar to those in 

 Fowler's papers. The headings are (a) length of animal in milli- 

 metres, (b) length of tail in mm , (c) length of tail as approxi- 

 mate percentage of total length, (d) number of jaws, (e) number 

 of anterior teeth, (f) number of posterior teeth. The tail fin is 

 not included in the following measurements : — 



9 Fowler — hoc. ci'., p. 2. 



10 Michael — Notes on the Identification of Chaetognaths. 

 .xv., 1908, No. 2. J 



(Biolog. Bull. 



