I'HE HESI'KKIIDES ol' J5RITTANY. l79 



It is interesting, though not very profitable in results, to carry 

 one's theories to any extent. Much still remains to be done by obser- 

 vation in the held. I was, however, fortunate enough one day to see 

 on the same bush, in the interior of British Guiana, specimens of 

 Li/con'a poiiiiuintia, L. rors, Melinaca rramcri, M. nnii'iiu', and [Jell- 

 conins rctiistns. ^^'ith their wings closed, unless one got very near, 

 all these appeared alike, and no opponent of any theory of mimicry 

 could deny that it was a distinct advantage to each individual speci- 

 men to be like many others. Heveral other species have since been 

 taken by my correspondent on the Potaro River, where I saw and took 

 my specimens, and very likely some have come oft" the large bush that 

 presented such a picture to my eyes. Whether any of the above are 

 palatable or not would make very little difterence ; all being so much 

 alike, they share each other's dangers from experimental attack. In 

 other words, it is a life insui-ance in which every species takes its share of 

 the risks. Such groups as this are numerous in the particular 

 locality cited, but I much doubt if a single instance of a Batesian case 

 exists. If the attack be experimental, and not persistent, it would be 

 merely accident if one species were palatable while another was not so. 

 What are the palatable species "? One hears the Pierines given, and 

 yet the vast majority of the Pierines are not protected by being like 

 other species which are not palatable. There are admittedly excep- 

 tions, as is seen in the $ s of the Mj/lutJiris species, which resemble 

 some Danaines and Ithomiines. Home members of the genus l>is- 

 viorplda are also well protected in both sexes, but if the Pierines were 

 in general sought after as tasty morsels, one would expect, at least, all 

 the large conspicuous species to be protected, but this is not appa- 

 rently the case. Large species of Vieria or DaptDHoura are often not 

 abundant, and rarely, if ever, have any ally for protection. If the 

 Miillerian theory is true (and it is very difticult not to accept the broad 

 lines), there is scarcely need for the Batesian theory at all, and our 

 hitherto so-called palatable and distasteful species may all have very 

 much the same flavour. 



The Hesperiides of Brittany. 



By CHARLES OBEKTHCK, F.E.S. 



I am interested to learn that Hesperia alvciis is reported to have 

 been found in England. I have always thought that this species 

 ought to be found in England, and I believe that some day you will 

 find ('arcliaroilm alccae, which is a very common species in Bretagne, 

 also on your south coast. In Bretagne, H. alreiis is very local, and 

 never abundant. It is to be found in the helds in the neighbourhood 

 of Rennes, particularly at the end of August and commencement of 

 Septenjber, but it is always difhcult to catch many specimens ; one 

 only meets with it in small numbers, usually singly. I have also 

 taken H. ain ns at the end of May and commencement of -June, but 

 even more rarely then than in August and September. 



The best locality, to my knowledge, in the department of lUe-et- 

 Vilaine, for //. alreii.s, is the dune of Miel-Pot, between St. Malo and Can- 

 cale ; this dune is formed of an " amas " of hard sand, covered with a rich 

 vegetation of L'osa pi tu/iinclU folia, I lev, Trifnliiiiii, (Jarr.r, Krijnfiinm 

 maritiwinii, &c. On this dune one finds //. alniis at the commence- 

 ment of June, and again from August 15th to September 10th, and 



