( 435 ) 



XX. Notes on the life-history of Porphyraspis tristis, 

 a palm-infesting Cassida from Brazil. By A. 

 Sidney Olliff. 



[Eead September 3rd, 1884.] 



The Cassida which I now have the pleasure of exhibiting 

 in all its stages was recently received by Lord Walsing- 

 ham in a small collection of insects formed by Mr. John 

 Cameron Grant in the neighbourhood of Bahia. My 

 attention was first called to this insect by observing the 

 curious excrementitious covering, closely resembling an 

 inverted bird's nest in miniature, with which the larva 

 protects itself from the heat of the sun. The species 

 proves to be the Porphiirasins tristis of Boheman,* 

 and is found not uncommonly feeding gregariously on 

 the tender portions of the leaves of the cocoa-nut palm, 

 to which it is said to do considerable damage. The 

 larva of this insect was brought before the notice of the 

 Society at a vecent meeting by Dr. David Sharp, who 

 does not, however, appear to have recognised the merdi- 

 gerous nature of its covering.! The larvse of many of 

 the Cassididce, as well as certain species of Crioceridce, 

 are well known to form for themselves a covering of their 

 excrement ; but I am not aware that any account has 

 been published of a coleopterous larva making a nest- 

 like habitation for itself, with the exception of Porphy- 

 raspis palmarum, Boheman, figured and described by 

 Candeze in his excellent paper on the Metamorphoses 

 of Exotic Coleoptera.I This larva forms a nest, which 

 it carries on its back, very similar in appearance to that 

 of P. tristis, and is found on a palm, supposed to be a 

 species of Thrinax, in the island of San Domingo. 

 I am incHned to think that this nest-forming habit 



- ' Monographia Cassididarum,' i., p. 95 (1850) ; Wageuer, MT. 

 Muncli. Eut. Ver., v., p. 53 (1881). 



f Cf. infra, Proc. Eut. Soc. Loud., 1884, p. xviii; 'Zoologist' (3) 

 viii.,p. 391 (1884). 



I Mem. Soc. Liege, xvi., p. 390, pi. v., fig. 5 (1861). 



TEANS. ENT. SOC. LOND. 1884. — PART III. (oCT.) 



