September 16, 1922] 



NA TURE 



373 



its predecessors, the present part is accompanied by a 

 magnificent series of plates and analytical figures of the 

 flowers and fruits of the various species, which very 

 materially enhance the value of the memoir. 



The genus Ceratolobus, which is confined to the 

 Malay Peninsula, Sumatra, Java and Borneo, consists 

 of six species, four of which are described by Beccari. 

 Three of these four are found in Borneo and two in the 

 Malay Peninsula — one of the later, C. laevigatas, Becc. 

 having six varietal forms spread over the Malay 

 Peninsula, Sumatra and Borneo. Calospatha Scor- 

 techinii, collected by that assiduous botanist, Father 

 Scortechini, in Perak, and described by Beccari, comes 

 next on the list and is an interesting and very distinct 

 palm, having a homogeneous albumen in the seeds, 

 two to three in a fruit. In the genus Plectocomia, 

 which are large, spinous, calamoid palms with terminal 

 inflorescences, six new species are described. One of 

 these, P. Kerrana, was discovered at Doi Soetep, near 

 Chiengmai, Siam, by Dr. Kerr, who has made known 

 to us the riches of the Siamese flora by his admirable 

 collections in that country. 



Plectocomiopsis is a new genus described by Beccari, 

 containing five species, from Lower Burma and through- 

 out the Malay Peninsula and Sumatra, and is again a 

 calamoid, dioecious genus allied to Myrialepis, Becc. In 

 its vegetative organs it resembles Plectocomia, though 

 it differs widely in the spadices and flowers. Beccari 

 then passes to the genus Zalacca, a characteristic and 

 exclusively Indo-Malayan group containing thirteen 

 species, denizens of rich, deep and moist soil in the 

 recesses of primaeval forests. The home of Z. edalis, 

 which is frequently cultivated for its edible acid fruits, 

 is not definitely known, but it is considered to be a 

 native of the Malay Islands. It has been known since 

 the time of Clusius, who examined fruits of this palm 

 sent over from Bali in brine about 1600. Two new 

 varieties of this species are described, and six new 

 species by Beccari ; of the latter, Z. dubia is only cer- 

 tainly known from the male flowers. 



The genus Pigafetta described by Beccari was 

 regarded by Martius as a section of Metroxylon, the 

 sago palm, but Beccari proves that it is a distinct 

 genus by its polycarpic nature. It is not closely allied 

 to any other genus of Lepidocaryeae, and is a tall tree 

 with dioecious, axillary spadices and small calamoid 

 fruits. It is due to these small fruits, no doubt, which 

 are eaten by birds, that this palm, P. filaris, has so 

 wide a range in the Moluccas, Celebes, New Guinea and 

 Indo-China. 



The next genus dealt with, Korthalsia, is again a 



genus of climbing palms containing twenty-six species, 



mainly Malayan. They are of economic use as, being 



very tough, the naked canes are used for tying, etc., by 



NO. 2759, VOL. I IO] 



the natives ; they are also of interest in being myrme- 

 cophilous, with the appendage at the mouth of the leaf 

 sheath (the ocrea) largely developed and sometimes 

 transformed into a closed ant nidus. Extra-floral 

 nectaries are also developed in the axillae of the leaflets. 



Metroxylon, the sago palm, and Eugeissona, one 

 species of which, E. utilis, Becc, also yields a sago 

 flour, complete the Asiatic LepidocaryeK, and the part 

 is concluded with an enumeration of the extra Asiatic 

 palms belonging to this family, among which Raphia 

 and Mauritia are perhaps the best-known genera. 



The genus Metroxylon contains six species with 

 numerous varieties, and the account of these valuable 

 palms occupies nearly forty pages of the memoir. They 

 are arborescent palms with a terminal inflorescence, 

 and the two best-known species are M. Rumphii and M. 

 Sagus, which are widely cultivated in the Moluccas, for 

 the sake of the starch or sago flour extracted from the 

 stem. Both these palms yield many other com- 

 modities used by the natives. Prof. Beccari considers 

 the Moluccas to be the home of these two species, and 

 especially the island of Ceram, where a new species, 

 M. squamosum, Becc, has been found in abundance at 

 the east end. Owing to their importance in affording 

 food to the natives, they have now been carried far 

 and wide. 



To appreciate the value of this work it must be 

 studied in detail, and all students of palms and botan- 

 ists generally will realise how much they have lost by 

 the death of Prof. Beccari, who was the pre-eminent 

 authority on palms. A. W. H. 



The Control of Electric Power. 



Switching Equipment for Power Control. By S. Q. 

 Hayes. Pp. vii + 463. (New York and London: 

 McGraw-Hill Book Co., Inc., 1921.) 205-. 



SOME of the most important problems with which 

 the engineer of a large power station has to 

 deal are in connexion with the switches and control 

 apparatus of his distribution system. Information 

 on this subject can be found in a very condensed 

 form in several text-books, but there is a demand 

 for more detailed information, and in particular there 

 is a great demand for a definite statement of the 

 physical principles on which many of these devices 

 are supposed to act. In Mr. S. Q. Hayes' book detailed 

 information is given of many types of switchgear of 

 American manufacture, but as a rule the descriptions 

 are similar to the descriptions we get in manufacturers' 

 catalogues, and in some cases they are actuallv taken 

 directly from these catalogues. The author is one of 

 the leading experts on switchgear, and occasionally 



M I 



