NA TURE 



457 



THURSDAY, MARCH 20, 1890. 



A NATURALIST IN NORTH CELEBES. 



A Naturalist in North Celebes. By Sydney J. Hickson, 

 M.A. (Cant), D.Sc. (Lond.), M.A. (Oxon. Hon.Caus.). 

 With Maps and Illustrations. Pp. 392. (London : 

 John Murray, 1889.) 



THIS book is the outcome of the residence of a 

 specialist for nearly a year upon a small island 

 off the extreme north point of Celebes. Of books of travel 

 there is in these days no lack, and so beaten are the 

 paths along which authors for the most part lead us, that 

 the reader in search of amusement or instruction not 

 infrequently arrives at the index without having met 

 with either. But Dr. Hickson's is not a book of travel: 

 it is a record of a naturalist's life with an almost bound- 

 less submarine field for observation close at hand — albeit 

 terrestrially somewhat limited — and when he leaves his 

 coral-girt island, it is to wander in that little-known archi- 

 pelago which links Celebes to the Philippines, the Sangir, 

 Nanusa,and Talaut groups, whither few but adventurous 

 Dutchmen have penetrated. 



Of the fourteen chapters, three are devoted to Talisse^ 

 the island on which Dr. Hickson conducted his observa- 

 tions. Four are descriptive of his wanderings in the 

 groups just mentioned, and the remainder for the most 

 part treat of the Minahassa district, its natives, and their 

 mythology and customs. Of these, the author tells us in 

 his preface that " the greater part of the ethnological 

 portion of the book is borrowed from the valuable writings 

 to be found in many of the reports of missionary and 

 other societies, and in Dutch periodicals." 



Dr. Hickson owing his voyage almost entirely to a 

 desire to study the corals of the Malay Archipelago, it is 

 naturally to that part of the book which treats of them 

 that we first turn. No one has ever yet done justice to 

 the wonderful beauties of coral-land, and the author, in 

 common with his predecessors, has failed — as everyone 

 must fail — to convey to the untravelled reader an adequate 

 idea of the appearance of a vigorous reef. Perhaps the 

 very fact of being an authority has lessened his chance of 

 success. The description is nevertheless a good one, and 

 the chapter (vi.) the most important in the book. Dr. 

 Hickson has wisely relegated his technical work to the 

 publications of the various learned societies, but he tells 

 us much of interest. The first sight of a coral reef at 

 close quarters astonished him — specialist as he was : — 



" I could not help gazing with wonder and admiration 

 on the marvellous sight. ... I had expected to see a 

 wonderful variety of graceful shapes in the branching 

 madrepores and the fan-like, feather-like alcyonarians, 

 . . . but I was not prepared to find such brilliancy and 

 variety of colour" (p. 15). 



That vexed and most important question, the growth 

 of coral reefs — a question upon which it was to be hoped 

 that Dr. Hickson might be able, from the length of his 

 stay and his varied opportunities, to enlighten us — is left 

 pretty much where it was. We should be able to pre- 

 dict with certainty the direction and the rapidity of 

 Vol. xli.— No. 1064. 



growth. As it is now, charts of coral islands and reefs 

 become almost valueless in the course of a few years. 

 But the causes both of growth and erosion are still un- 

 determined. Much, no doubt, depends upon the rapidity 

 of the tides. In strong tide-races no true coral reef is 

 ever formed. " Flowing water, which is neither too swift 

 nor too stagnant, bearing the kind of food necessary for 

 the proper nourishment of the corals," is, as Dr. Hick- 

 son justly remarks, a strongly predisposing element to 

 vigorous growth. Yet this is not always the case, neither 

 does the converse always hold good ; and we cannot 

 agree entirely with the author when he says, "in deep 

 bays or inlets, where tidal and ocean currents are 

 scarcely felt, there is but little vigour in the reef." The 

 inner harbour of Amboyna displays as rich a " sea 

 garden," perhaps, as any in Malayan seas. 



Dr. Hickson's 'daily work on the reefs led him to the 

 certain conclusion that but one true species of Tubipora 

 exists. The size of the tubes and the character of the 

 septa — upon which most of the species are founded— are 

 shown to be utterly without specific value ; these differ- 

 ences depending entirely upon the position of the coral 

 on the reefs. The following remarks upon a fact which 

 must have struck most naturalists in tropic seas, but 

 which we do not remember ever to have seen in print 

 before, are worthy of quotation. Talking of sunrise and 

 early morning, he says : — 



" Not only are the birds and insects, which disappear 

 as the sun becomes more powerful, particularly visible at 

 that hour, but it is the time of day above all others 

 when the surface of the sea teems with animal life. I 

 remember well my disappointment when I first got into 

 tropical waters at finding that my surface-net invariably 

 came up almost empty. It was not until I had been at 

 work some time that I made the very simple discovery 

 that in the early morning hours every sweep of the net 

 brings up countless pelagic forms of all sizes and descrip- 

 tions " (p. 58). 



The question of the food of corals is yet unsettled ; but 

 the author, after careful examination of polypes of various 

 kinds, is inclined to the behef that many of them may be, 

 partially at least, vegetable feeders. No doubt the water 

 in the vicinity of mangrove-swamps is very largely charged 

 with the debris of leaves and fruit and wood, some of 

 which, sinking to the bottom, must enter the mouths of 

 the polypes. Upon the mesenterial filaments of the 

 Alcyonarians, indeed, particles of vegetable fibre are 

 frequently found. It is suggested that the vigorous reefs 

 frequently seen near extensive swamps, may be explained 

 by such an hypothesis. Upon Darwin's theory of the 

 formation of atolls. Dr. Hickson had little opportunity of 

 forming an opinion — little, at least, until he visited the 

 archipelagos already mentioned. He ultimately came to 

 a disbelief in the general subsidence theory, and is not 

 opposed to Mr. Murray's view — that coral reefs can, 

 under favourable circumstances, grow out into deep sea- 

 water upon the talus of their own ddbris. 



Among many references to birds occurs an account 

 (p. 41) of the existence of the maleo, or brush-turkey, in 

 Ruang Island. Unfortunately, we are not told whether 

 this is Mei^acephalo?t maleo, or the smaller Megapodius 

 gilberti. They were most probably the latter ; but it 

 would be interesting to know, for the true Megacephalon 

 of Celebes has never, we believe, been recorded as 



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