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Carnivorous plants exploit animals as a nutritional source and have inspired long-standing questions about the origin and evolution of carnivory-related traits. To investigate the molecular bases of carnivory, we sequenced the genome of the heterophyllous pitcher plant Cephalotus follicularis, in which we succeeded in regulating the developmental switch between carnivorous and non-carnivorous leaves. Transcriptome comparison of the two leaf types and gene repertoire analysis identified genetic changes associated with prey attraction, capture, digestion and nutrient absorption. Analysis of digestive fluid proteins from C. follicularis and three other carnivorous plants with independent carnivorous origins revealed repeated co-options of stress-responsive protein lineages coupled with convergent amino acid substitutions to acquire digestive physiology. These results imply constraints on the available routes to evolve plant carnivory.

Powdery mildew is reported for the first time on the Albany pitcher plant (Cephalotus follicularis). The plants originated from a nursery in Melbourne. The fungus was identified as Podosphaera xanthii using morphological characters and a rDNA ITS sequence. This is the first record of powdery mildew on the Cephalotaceae.

PROF. JOHN MTJIRHEAD MACFARLANE, emeritus professor of botany in the University of Pennsylvania, died at his home in Philadelphia a few weeks ago. He was born in Kirkcaldy in 1855, and his work was over more than twenty years ago. One or two old friends still remember him when he and they were boys in Edinburgh, where he learned his botany from “Woody Fibre” and from Alexander Dickson, and became one of Bayley Balfour's first assistants. It was under Balfour's influence that he wrote his once well-known paper on the minute structure of plant hybrids, which remained perhaps his chief work to the end. It was a careful comparison, within the histological limitations of its day, between the tissues of various hybrids and their parents, in such curious cases as the so-called Philageria (that is, Lapageria x Philesia) Veitchii, and the famous 'graft-hybrid', Cytisus Adami. This investigation led to his first appointment in the University of Pennsylvania in 1892, and gained him the Banksian Medal of the Royal Horticultural Society a little later on. His old master Dickson had been interested in pitcher-plants, and the Edinburgh Garden was rich in these, in cluding the rare little Cephalotus and many hybrid Sarracenias and other things. Macfarlane had a note in NATURE on honey-glands in pitcher-plants, nearly sixty years ago. Long afterwards he did the pitcher - plants for various Floras, including those of British North Borneo and of New Guinea, and he wrote the chapters on Nepenthes, Sarracenia and Cephalotus for Engler. He was a very faithful and a very industrious man.

I OBSERVE that the last sentence but one of my brief notice of Cephalotus, which appeared in NATURE last week, is calculated to convey an erroneous impression. The lid g of Fig. 1 is seen to be a conical structure with a relatively broad base and a narrower indented apex. In the matured pitcher the free portion of the lid is much broader than its more contracted base; and the developed and involuted margin referred to extends round the mouth of the pitcher until it reaches that base, but does not cross it, as by an oversight on my part my words imply.