Thanks for 'Proceedings'; books required; he would like a description of rodents he presented to the Society; his manuscript notes only given habitat; a South American species; he knows it has been taken on the 'Beagle' voyage; Darwin sends his specimens to Cambridge; another specimen, a Peruvian cavy, presented to a 'Beagle' officer by an American sealing officer, Cutler; if it is new, he proposes 'Cutleri' as the name; another cavy from the east coast of Patagonia; he has distributed small tubes with alcohol for collecting Australian specimens; '...thanks for your kindness in looking over my novelties before the Beagle's return places them altogether on the shelf of useless lumber.'