1910.1 89 



Female. — The seventh sternite is much narrower at the apex in franciscanus 

 (fig. 3) than in ignotus. Both insects vary rather much in the nvunber of 

 bristles on the thorax and abdomen, but ignotus has generally more bristles 

 than franciscanus. On the first abdominal sternite, for instance, ignotus has 

 several hairs at the ventral margin between the postmedian ventral bristle and 

 the base, while franciscanus is usually devoid of any hairs in that place. The 

 ninth abdominal tergite in ignotus has more than 25 bristles on the lateral 

 ventral portion and only about 20 in francisc amis. 



Hah. : San Francisco, California, off Tlwmomys bottai ; a small 

 series of both sexes. 



Tring Park, Tring : 



February, 1910. 



Galcrucclla nymphsese and sagittarise. — An luifoi'tunate confusion exists 

 about these insects, viz., first as to their characters and distinctness, and next 

 as to their names. We have many of us recognised two species in this country, 

 and have called them nijmphieie, L., and sagittarise, Gyll. Doiibts have, however, 

 been expressed as to the distinctness of the two forms by Fowler (Brit. Col. 

 iv, p. 329) and others, and Bedel in his " Faune Col. Bass. Seine," v, p. 278, 

 treats sagittarise as merely a variety of nymphsese. 



I think there are certainly two very variable, but distinct species : nymphsese 

 is broader, has a markedly larger head, and the cox£e, more especially the hind 

 pair, are more widely separated. The variation of the two forms is different, 

 and nymphsese lives only on water-lilies, while sagittarise eats a variety of plants, 

 but apparently excludes water-lilies from its diet. They are both very variable, 

 and it is necessary to bear this in mind in considering the question of their 

 names. Gyllenhal descx-ibos two species under the names I have given at the 

 head of this paper, and there is no reasonable dovibt as to his intention of 

 referring to oiu- two forms, though he did not fvdly appreciate the variation 

 and the true distinguishing characters, and the same remark applies to C. J. 

 Thomson, who treated of a similar fauna in 1866 (Skand. Col. viii, p. 157). 

 Weise, in 1888, also adopted two species with the same names (Ins. Deutschl. 

 vi, p. 624) ; he, however, relied largely on the acuminate apices of the elytra of 

 nymphsese for distinguishing them, and he gives a note expressing a little, but 

 not much, doubt about the species Gyllenhal referred to. Weise was wrong in 

 attaching much importance to the acximination of the elytral tips, as this is a 

 highly variable character, and is sometimes nearly as strongly marked in 

 sagittarise as it is in nymphsese; the two elytra, moreover, are occasionally 

 differently shaped in the same individual. 



Bedel, in the work already referred to, abandoned the species sagittarise as 

 a mere variety, but stated, in giving the synonymy, that Weise's sagittarise was 

 not the sagittarise of Gyllenhal. He gives no reason, bvit I presmue he was 

 misled by the note of hesitation given out by Weise and already mentioned 

 above. 



