26 



an introduced plant, but had no doubt of its identity with Australian 

 specimens. 



The Hon. Mr. Hall thought the Australian burr must have been 

 introduced by imported cattle. 



7. " On the Salmonid?e of ISTew Zealand," by Dr. Hector. (See 

 Transactions.) The author called attention to the importance of knowing 

 what fish belonging to this order were indigenous to the New Zealand 

 streams, as the English trout is now firmly established in many of the 

 streams of the South Island, and as they will probably undergo, as they 

 usually do in all streams, considerable modification of form, mistakes 

 might arise from their being confounded with nearly allied fish which we 

 already possess. This investigation is more necessary as the best and 

 latest works only describe one species of the Salmonidse, as occurring in 

 New Zealand, viz., Retropinna Ricliarsonii. The author, after describing 

 the character of this species, and identifying it with specimens on the 

 table, exhibited three other very distinctive forms. The first of them 

 had a general resemblance to the above specimen, but is four times the 

 size, and possesses some of the external characters of a true Osmerus, or 

 English smelt. The specimens he exhibited were obtained from the 

 Kakapo Lake, on the west coast of Otago, in 1863. 



The third species was the common Opokororo, from the Hutt river. This 

 fish is at once distinguished from the others by the small head, large deep 

 body, dark trout colour, forward position of the dorsal fin, and small sofb 

 mouth almost devoid of teeth. In some of its characters it approaches the 

 genus Coregonus, to which the White fish of the North American Lakes 

 belongs. It was pointed out that notwithstanding the very marked difier- 

 ences which are such as to characterize difierent genera of European fish, 

 certain external characters, s\ich as the number of the rays in the fins, were 

 common to all these forms ; the only exception being in the pectoral fin, in 

 which the last anentioned fish had fifteen instead of eleven rays. We are 

 thus placed in a dilemma, as either there is only one species which under- 

 goes most extreme variations, so as to simulate difierent genera, or we 

 have three different genera, the representatives of which in New Zealand 

 accidentally possess some trivial characters. 



The subject deserves the attention of observers, and the author hoped 

 he would be assisted in the investigation by the collection of specimens 

 from different streams in the country, before it was complicated by the 

 introduction of foreign species of trout. He stated, for the assistance 

 of collectors, that the Salmonidse could be distinguished from all other 

 fish in our streams, by the little fleshy fin that they have between the 

 large dorsal fin and the tail. 



