Responds to CD’s two objections to the principles involved in the "Rules of zoological nomenclature": (1) that strict enforcement of the rule of priority would cause much inconvenience, and (2) attaching name of the first describer in perpetuity puts a premium on careless description by "species mongers".

Physical description of Sikkim mountains.

Travelling through Kinchin snows.

Transported boulders.

Continues prior letter of this date. Has received CD’s [1202]. Thanks CD for saving his correspondence.

Sent "a yarn about species" in October mail.

Some "puerile" JDH letters printed in Athenæum.

Requests CD extract anything valuable from his letters to CD and Lyell for Athenæum.

CD’s complemental males in barnacles wonderful.

Warns CD to drop his battle about perpetuity of names in species descriptions.

The priority rule has only diverted vanity to a rush to be first. Has no objection to CD’s suggestion that good books be quoted in preference to first descriptions if there is a chance by this means of developing this silly vanity into ambition to advance knowledge. Still, this must not affect the rule of priority. Responds to CD’s four cases.

Clarifies the notion and use of type-species and applies it to CD’s problem with Conchoderma.

On domestication of pigeons and hybrid geese.

Pleasure at receiving CD’s scientific letters to JDH and Hodgson.

The H. Wedgwoods’ pecuniary loss.

Condolences at CD’s father’s death.

Rajah harasses JDH’s work. Lack of supplies, rain, malarial valleys, and landslips make going difficult. Cannot get into Tibet.

"Twenty species [of plants] here [Camp Sikkim] to one there [Tierra del Fuego?] always are asking me the vexed question, ""where do we come from?""."

From observation of terraces descending to steppes and plains of India, he thinks that the Himalayas were once a grand fiord coast.

Has information CD requested on Yangsma valley. JDH’s detailed hypothesis of origin of dam there. Does not agree with CD’s interpretation.

CD partly right. JDH was calling "stratification" what CD calls "foliation". Answers CD’s question on cleavage foliation in Himalayas. Glacial action.

Charmed by CD’s Admiralty instructions on geology [in Manual of scientific enquiry (1849), Collected papers 1: 227–50], but complains he does not give prices of books and instruments he recommends.

Has sent all the fossil pedunculated cirripedes in the Copenhagen collection, together with a letter from Johannes Steenstrup concerning changes he believes are needed in the descriptions.