PEEFACE. 



This Twentieth Decade completes the Second Volume of the 

 Prodromus of the Zoology of Victoria. 



A systematic index is given of the contents of the first twenty 

 Decades, comprising plates 1 to 200, combining the contents of 

 the hrst and second volumes, according to which the plates with 

 tlieu" corresponding letterpress may be bound in zoological order, 

 all the illustrations of each class being put together by those 

 who desire it. Those who prefer to bind the plates and corre- 

 . spending letterpress in the order of their original appearance, and 

 as the plates are consecutively numbered, can do so, bringing 

 the prefaces together at the front. An alphabetical index is also 

 given of the contents ; the generic, specific, and popular names 

 being included, as well as the synonyms, M'hich latter are in 

 italics. 



I am greatly indebted to Mr. Simons for the high intelligence 

 and painstaking accuracy with which he did me the favour to 

 prepare these Indices — a task so onerous that I feel very grateful 

 for his friendly help in relieving me of it — and with such care 

 that they materially increase the value of these volumes. 



The first plate in this Twentieth Decade represents two of 

 the commonest of the beautiful small lizards constituting the 

 genus Hinulia, with magnified details. 



The second plate gives for the first time the colours of life of 

 a lovely species of Dragonet, as similar fishes are called in 

 England, not uncommon in Hobson's Bay, the Callionymios 

 calauropomus (Rich. ). 



The third plate figures for the first time a beautiful kind of 

 Red Gurnet-Perch, the Neosebastes Scorpcenoides of Guichenot, 

 not uncommon in the fish shops all the year round. 



