Has put question of proportion of sexes in insects to the Entomological Society. Quotes H. T. Stainton and F. Smith. Cites some cases mentioned by other members.
Is reading Variation; does not quite understand Pangenesis.
Royal Geographical Society | 15, Whitehall Place, S.W.
My dear M
I could not myself remember any case of female insects being very conspicuously more numerous than the males & therefore put the question, as you desired to the Entomological Society, last night. Some facts & good opinions were elicited:—
Other members gave these cases:—
Tomicus villosus (bark Coleopter of the oak)
no male found by Ratzeburg during many years observation
Tomicus dispar— an English species
males exceedingly rare
Miana arcuosa— an English moth—
males fly in great
numbers over damp meadows in many places—females only
one or two in a season
an English Neuropterous insect
hundreds of females found
during last two years— no male yet found
In Hemerobiidæ according to Maclachlan females are much more numerously found than the males.
One of the above cases I have mentioned by mistake—it being the reverse illustration—males more numerous than females.— Plenty of cases can be mentioned of males occurring more numerous; but after the strongly expressed opinions of Stainton & Smith & the case of the Tineina (which was confirmed by other able observers, Mr F. Bond among them) I must say I shall hereafter hesitate to accept any fact, without reserve, of sexual disparity in numbers without the species are actually bred. Although the cases of vast majority of ♂ butterflies in hot countries seem pretty clear, yet it is possible the females may, in some unaccountable manner, elude observation.
Perhaps in selecting species for figuring in your next work, it would be better to chose the most wonderful, altho' they may not be British. The Chilian stag beetle Chiasognathus, would surprise people more than our common insect. I am now reading your two Volumes. Pangenesis I have read once & must read again before I thoroughly understand it. A friend tells me the same.
Yours sincerely | H W Bates
- f1 5893.f1CD requested information on the proportion of the sexes in insects in his letter to Bates of 11 February . Bates had put the question to the meeting of the Entomological Society of London on 17 February 1868. The ensuing discussion was reported in the society's Transactions for 1868, pp. x--xi, and is summarised in Descent 1: 310.
- f2 5893.f2Henry Tibbats Stainton had published extensively on the Tineina moths (ODNB). Tineina was a taxon defined by Stainton as comprising fifteen families of Lepidoptera including the smallest known moths (see Stainton 1867, pp. 59--60, 84--8). The name Tineina is not used in modern taxonomy. CD cited Stainton on the proportion of the sexes in the smaller moths in Descent 1: 310.
- f3 5893.f3The results of Frederick Smith's breeding experiments with sawflies (Tenthredinidae) are reported in Descent 1: 314.
- f4 5893.f4CD reported the remarks of Edward Westey Janson on the preponderance of females in the bark-eating beetle Tomicus villosus (now Dryocoetes villosus) in Descent 1: 314.
- f5 5893.f5Julius Theodor Christian Ratzeburg was an expert on forest insects.
- f6 5893.f6Tomicus dispar is now Xyleborus dispar.
- f7 5893.f7Miana arcuosa is now Photedes minima (small dotted buff).
- f8 5893.f8Apatania muliebris is now in the order Trichoptera (caddisflies).
- f9 5893.f9The family Hemerobiidae (brown lacewings) is in the order Neuroptera. Bates refers to Robert MacLachlan.
- f10 5893.f10Frederick Bond.
- f11 5893.f11Bates refers to Chiasognathus grantii. See letter to H. W. Bates, 11 February  and n. 8.
- f12 5893.f12The reference is to the chapter `Provisional hypothesis of pangenesis' in Variation 2: 357--404.