British Museum.
10 Novr. 1857
My dear Sir
Some time ago you asked me to furnish you with remarkable instances of desparity in form etc—in workers of Insects living in community—1 As one is apt to forget these things at the moment they are asked for I send you one that is a truly remarkable instance— In my Monograph on the Genus Cryptocerus I figured & described a species as C. discocephalus—2 some time subsequent I received a letter from Mr. H. W. Bates from Brazil—3 he said—“I have met with your curious species C. discocephalus— the creature figured is only the large size of the worker of the species— I send you both the workers taken from several nests constructed in dead branches of shrubs—”
I send you tracings of the creatures in relative proportion— dont trouble to reply to this but tell me what you think of it when you are next time at the Museum4 and believe me
Yours very truly | Fredk Smith Chas. Darwin Esqre
Please cite as “DCP-LETT-2167,” in Ɛpsilon: The Charles Darwin Collection accessed on