My dear Sir

I am obliged for all you have done for me.—

The woodcuts¹ require but trifling alterations; & I have appended full instructions: please send me a tracing of the lower or altered part of No I, when you have altered the drawing.—

I send a fine specimen of scutum of P. validus which will be easier for you to draw from, than that which you already have.—

I will first tell you what additional figures I must have done, & then we will discuss how it can be done.— But first observe that I find from fresh specimens that I have probably confounded two distinct species under name of S.(?). undulatum;² —if the figures of this species are engraved, there will be some unavoidable confusion in the placing of the figures.— Of new figures, I sh^d. like;

[Diagram]

(1).P. Nilssonii, scutum, quite small & simple; if that c^d be introduced near the carina & two other valves, it w^d be a great advantage³

(2).Scalpellum undulatum. carina long & narrow

(3). do. do. do, lateral view of short upper portion.

(4) do. do. —— section of upperportion. quite small

(5). do. do. Carinal Latus, small; this might be done as a woodcut if you are much pressed for room.—

Again if these can go with the tergum it w^d be best, but probab- ly it will be too late.

(6) Scalpellum semiporcatum scutum of medium or even small size:⁴ this ought to be introduced near S. tuberculatum & Oxynaspis cretæ; but of course this does not signify much.—

even this might be done as woodcut, I think. [/Diagram]

I send diagrams as before of all these new figures.—

Now if you must leave out some other figures to introduce these, please leave out all four figures of P. Hausmanni—⁵ Or could you manage (which I should prefer) by leaving out only Fig 2 of P. Hausmanni & fig. 4 of P. carinatus & fig 5 of P dorsatus.?— You told me you had introduced some figures not directed by me could you leave out any such, & thus gain space.— I am sure you will endeavour to do what you can to oblige me: please to observe that any extra work beyond your Estimate with Pal. Soc. will of course be paid for, by communicating with M^r Bowerbank, to whom I have written stating that a few extra figures would be required.— Please to keep an account of any charges for Carriage.—

I hope to God I have now come to the end of my specimens.—

When your Plates are all engraved & I have proof-sheets, I will come to London & compare specimens at Park St & so avoid having so much writing to you.— I sh^d. be glad to know some days before the Proofs are ready, that I might arrange my plans accordingly

My dear Sir | Your’s very faithfully | C. Darwin