THH comments on G. A. Brullé’s paper ["Researches upon the transformations of the appendages of the Articulata", Ann. & Mag. Nat. Hist. 13 (1844): 484–6].

On classification and possibilities of a scientific morphology and zoology. CD’s "pedigree business" is important for physiology but has nothing to do with pure zoology any more than human pedigree has to do with the census. Zoological classification is a census of the animal world.

K. E. von Baer’s view of the air bladder of fishes.

Serial homologies in the Mollusca. Gives instances of repetition of homological parts in Radiata.

Has just finished Origin. CD has demonstrated a true cause for the production of species.

CD has loaded himself with unnecessary difficulty in adopting natura non facit saltum.

Thanks for report [on echinoderms, Ann. & Mag. Nat. Hist. 2d ser. 8 (1851): 1–19]. Wanted to learn about metamorphosis of the class. Agrees with THH’s distinction between individuals and zooids, but thinks zooids will never cease to be called individuals.

Testimonial for THH’s application for Chair in Natural History at Toronto.

Proposes to send THH vol. 1 of Living Cirripedia.

On THH’s paper on cephalous Mollusca [Philos. Trans. R. Soc. Lond. 143 (1853) pt 1: 29–66]. Discovery of the type or "idea" (in THH’s sense, not Owen’s or Agassiz’s) is one of the highest ends of natural history.

Discusses anamorphism;

position of heart in Cleodora.

Variability within species;

cementing process in cirripedes.

Offers to send Ascidia specimens of Beagle voyage. Describes some of them.

Hopes THH will review his book [Living Cirripedia, vol. 1] which has been published for a year with no notice taken of it except briefly by Dana.

Discusses Limulus-like larva. "I have become a man of one idea.– cirripedes morning & night."

Second Living Cirripedia volume published. Asks THH’s advice on presentation copies for continental naturalists.

THH’s review of Vestiges of creation in [Br. & Foreign Med.-Chir. Rev. 13 (1854)]. CD is almost as unorthodox on species as the author of Vestiges, but hopes not quite so unphilosophical.

Hopes L. Agassiz was sounder on embryological stages than THH thinks.

Agrees with THH on metamorphosis of branchiae of Balanus, and on his view of Owen.

Thanks for help on presentation copies of Living Cirripedia, vol. 2.

Suggests he examine cementing apparatus of Balanus.

Sends specimens of sessile cirripedes for corroboration of their cementing apparatus.

Absence of anus in Brachiopoda and Alcippe cirripedes.

Thanks THH for corroborating his observations. Discusses metamorphosis of ovaria to cement organs. Ovaries, germinal vesicles, and anatomy of cirripedes. Difficulties of classification, and observation.

THH’s article on Mollusca [Charles Knight, ed., English cyclopædia: a new dictionary of universal knowledge (1854–70) 3: 855–74].

Thinks J. O. Westwood deserves Royal Society’s Gold Medal. Asks THH’s opinion of his nomination. Lyell deserves Copley Medal, but, since he has Royal Medal, it may be objectionable to propose him.

Thomas Bell thinks John Lindley superior for Royal Society Medal. CD agrees, but demurs at Medal going to same branch of science two years in succession.

Perplexed about Albany Hancock’s qualifications compared with J. O. Westwood’s.

Death of H. De la Beche.

Asks whether THH will attend Council of Royal Society and speak for him on Joachim Barrande and J. D. Dana.

Responds to THH’s questioning of his observations on cirripede anatomy with extensive discussion of what he observed. Admits his elementary knowledge of microscopical structures but seriously doubts he has erred. Cement glands, ovarian tubes, etc.

Approves drawing. No one who cannot draw should attempt to be a naturalist. Suggests corrections to [Lepas?] drawing. Comments on position of ganglia, cement glands, and stomach.