254 JOURNAL OF SCIENCE. 



P.S — Since 1 wrote ray short notes on the geographical relations 

 of our mollusca, I collected a number of Unio in the River Avon, and 

 amongst them I found six to be in a spawning condition. About one- 

 third, the central part, of the internal branchiae was entirely filled up 

 with the small white embryos, just in the same way as is the case with 

 the Najjadce of the Northern Hemisphere. The embryos showed the 

 same aspect as those of the Unio from Albury Creek. The external 

 branchiae contained a few scattered embryos only. 



T said that our Carthcea Kiwi belonged to the family of the 

 Orthalieida\ In saying so I followed Mr. T. F. Cheeseman, who placed 

 our shell in this family (Trans. N.Z. Inst., XIX., p. 170). This is no 

 doubt a mistake. The other clay I studied the dentition of C. Kiwi, 

 described and figured by Prof. F. W. Hutton in vol. XVI. of the 

 Transactions, and I have come to the conclusion that it belongs to the 

 genus Bidimulus, Leach, sub-genus Orthotomium, C. ik F., section 

 liliabdotus, Albers, of which about five representatives are found in 

 Chile. — IT. Suter. 



REVIEW. 



Introductory Class-Book of Botany, for use in New Zealand Schools. 

 By George M. Thomson, F.L.S., Science Master in the Dunedin High 



Schools. (Wellington, Didsbnry, 1891.) 



Mr. Thomson has produced a book which ought to be of great 

 use to science teachers. The ordinary text books of Botany are 

 concerned in great measure with the plants of the Northern Hemi- 

 sphere, and without access to large and costly original works it is 

 often extremely difficult to get any information about the common 

 native plants. On the other hand so many Northern forms are now 

 thoroughly acclimatised that a book dealing only with natives would 

 lie of limited application. Mr. Thomson has wisely selected his types 

 partly from the native, partly from the introduced flora of the Colony, 

 and his book is therefore one which should be useful both in districts 

 like Dunedin, where native plants are still abundant, and in those 

 like Christchurch, in which only introduced forms are to be had. 



The descriptions are clear and accurate, and are illustrated by 

 three plates and by no fewer than 227 woodcuts interspersed in the 

 text. The only fault one can find in them is one for which the 

 author is not responsible — they are often very badly printed ; the 

 drawing, however, is excellent, and the numerous sections of flowers 

 and of pistils, figures of anthers, floral diagrams, etc , are just such as 

 are required to aid the student who uses the book as it ought to 

 be used — with the plants before him and with pocket-knife and 

 magnifying glass ready to hand. 



A great deal of useful and suggestive information is given 

 incidentally about such branches of the subject as insect-fertilisation, 



