CANARIAN COLEOPIEEA, 437 



to establish races which are permanent, although included within ex- 

 ceedingly narrow limits. Thus, on the low sandy isthmus of Grand 

 Canary, between Las Palmas and the Isleta, where the insect abounds, 

 the specimens have usually their discal and lateral keels more or less 

 traceable (though often very obscurely so), whilst occasionally there 

 are faint indications of even the second one. The Gomeran examples, 

 judging from a type now before me which was captured by Dr. Crotch, 

 have the discal carina pretty evident, but the others hardly percep- 

 tible ; whilst a large array of individuals from Teneriflfe, which were 

 met with by Mr. Gray and myself near S'" Cruz, have all the ridges 

 entirely effaced. This last state has Likewise been communicated, 

 from Teneriife, by the Barao do Castello de Paiva. 



Apart from this peculiarity of the elytral costae, which are either 

 very indistinct or else totally obsolete, the Z. hicarinata may be known 

 by its rather rounded outline and light sculpture. In Grand Canary 

 its surface is generally of an intenser black than in Teneriffe — having 

 in the former case, more frequently, a just perceptible subcyaneous, 

 and in the latter a subaenescent tinge. 



It is barely possible that what I have treated as the state " o " 

 may be specifically distinct, but I think that its few diiferential cha- 

 racters are not constant enough to render such probable. I captured 

 it near to Maspalomas, in the south of Grand Canary ; and it recedes 

 from the state " a " (found in the north of that island) in having its 

 head and prothorax a trifle less alutaceous and rather more evidently 

 punctured, and in its elytra being more or less uneven, or malleated. 

 This inequality of the surface makes it difficult to decide whether the 

 obscure keels are developed, or not ; but the lateral one in some ex- 

 amples appears to be weU expressed, whilst in others it is scarcely 

 traceable. 



Fam. 63. ERODIAD^. 



Genus 259. ARTHRODES. 

 Solier, Ann. de la Soc. Ent. de France, iii. 513 [script. Arthrodeis] (1834). 

 Although M. Brulle consigns aU the Canarian members of this 

 famUy to Erod'ms, citing only one of them (his E. sid>costatus) as refer- 

 able to (what he would seem to regard as the suftgenus) "ArtJirodeis,'" 

 nevertheless, after a most careful inspection of them, I am satisfied 

 that they are aU* exponents of a single group — differing mainly from 



* Whilst asserting, however, that they are " all " exponents of a single group, 

 I do not mean to include that particular species (whatsoever it may be) wliich M. 

 Brulle cited (p. 63) as the "Eroditis europeus, Fab.," and which (whether rightly 



