To James Grant   2 May 1882

Melbourne, 2 May 1882.

The honorable the Chief Secretary.

Sir.

I have the honor to acknowledge the receipt of your communication of yesterday¹ accompanied by a sample of poison-herb, which proved detrimental to some pigs at Caulfield. With a view of ascertaining particulars of the case and inspecting the locality, I proceeded to Mr T. W. Nicholson's estate, where the poisoning case occurred. The plant, to which the mischief has to be adscribed is a tall umbelliferous herb, well known botanically since the last fourty years as Didiscus pilosus; but altho' this plant is sparsely distributed from Port Phillip through some of the inland-regions to near the Gulf of Carpentaria² northward and to Swan-River³ westward, and also extends to the north of Tasmania, — no record exists, — so far as I am aware —, of any injury to pastoral animals ever having arisen from this herb; notwithstanding that the plant abounded about 30 years ago on the now bare sands between Melbourne and Sandridge,⁴ where stock then used to browse, it actually passing at that time under the treacherous name of "native Parsnip". — As this Didiscus is fortunately biennial only, it would become suppressed by preventing it from flowering. — On enquiry I heard at Mr. Nicholson's place, that a number of half-grown pigs, to which the Didiscus-plant was given, — (as additional green-feed, under the idea, that it was similar to the Carrot-plant) — had died in a day or a day and a half, the animals readily devouring the luxuriant foliage. The symptoms produced were vomiting and purging, which set in some hours afterwards; but, as far as I can learn, no paralysis was produced For ascertaining any after-death appearances no dissections were made by Mr Nicholson's people. The poison seems to have acted so virulently, that a single plant, though only partly devoured sufficed to cause the death of two pigs. As in this instance we have to do with an absolutely new kind of poison-plant, which moreover has in various parts of Australia and even in new Caledonia several congeners of doubtless equally deleterious property, it will be important to find out, what precise chemical principle operates so powerfully and so unexpectedly in this innocent-looking herb. With this view I have placed myself in communication with W. Johnson Esq., the Government analytic Chemist, who with the facilities at his command has kindly undertaken, to search for and isolate the poison-principle, as I suspect, that it will turn out to be analogous to Coniin and Cicutin among the Umbelliferae and therefore a volatile Alkaloid. It is also my intention with the cooperation of a leading Veterinary Surgeon to investigate the physiologic action of this new vegetable poison on animals, to trace the post-mortem appearances and thus to devise antidotes; and more, — as providence does not call forth organisms of any kind without some beneficent purpose, we may also now obtain a clue, how this new vegetable principle could become a powerful therapeutic auxiliary perhaps in the hand of physicians, to alleviate or even subdue human maladies.

I have the honour to be, Sir,

your obedient servant

Ferd. von Mueller.

Didiscus pilosus

Umbelliferae