TWO NEW THOMISIDS — RAINBOW. 
169 
TWO NEW THOMISIDS. 
By W. J. Rainbow, F.L.S., Entomologist. 
(Plate xxx.) 
The present paper contains descriptions of two new species of 
Thomisidse, exceedingly interesting forms. The first, for which I 
propose the name Misumena tristania , was collected by Mrs. C. T. 
Starkey, of Neutral Bay, Sydney, at Cobbity, and presented by her 
to the Trustees. The spider was found upon some flowers of 
Tristania laurina , R. Br. (N.O. Myrtacese) a tali shrub or small 
tree, which (according to Mr. J. H. Maiden, Director of the 
Botanical Gardens, Sydney, who kindly identified the flowers for 
me), is found near watercourses, and is not uncommon in mountain 
gullies. The flowers of this shrub are bright yellow, and the 
colour is closely simulated by the spider, so that, unless it happens 
to move, it is difficult to detect. And, to colour must be added 
the form of the animal itself, when studying it in connection with 
the question of mimicry, because, when at rest, the body is posed 
in such a manner as to add greatly to the effect. The mimetic 
resemblance, therefore, must be regarded as ‘protective and attractive : 
the former, because it would assist the Arachnid in evading insecti- 
vorous foes, and the latter, because it would be the means of 
attracting insects upon which it feeds. 
The second species, Saccodomus formivorus , is remarkable 
not alone on account of its form, but also for the reason that, 
contrary to all previously recorded facts based upon accurate 
observations of the habits of the Thomisidse, it constructs a bag- 
like nest. It is in consideration of this, that in founding the 
genus diagnosed below, I propose the generic term Saccodomus . 
It has long been regarded as an axiom that all those individuals 
and species embraced within the vast family Thomisidse, popularly 
known as “Crab” or “ Flower” Spiders, are essentially wanderers, 
constructing neither webs nor nests for the capture of prey, but- 
relying solely upon their activity, cunning, or mimetic resemblance 
to surrounding objects. 
Another interesting feature in connection with this species is 
its food. Both Mr. W. W. Froggatt and Mr. George Masters, 
in speaking to me upon the subject, said that so far as their 
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