August 25, 192 1] 



NATURE 



823 



The diminutive shrunken heads made by the 

 Jivaro Indians have long been familiar objects in 

 our museums. In Natural History (vol. xxi., No. 2) 

 Mr. C. W. Mead gives an account of how and why 

 they were made. The head, with a small part of 

 the neck, is severed from the body. A cut is made 

 from the base of the skull down through the neck, 

 and through the opening thus made the bones of the 

 skull are carefully removed. The skin and the re- 

 maining soft parts are next dipped in the juice of 

 the huito fruit, which stains them black. The skin 

 is then ready for the shrinking process. This is done 

 by putting a number of hot stones into the cavity 

 and constantly turning the head in order to bring all 

 parts in contact with the stones. This process is 

 repeated until the head is reduced to the required 

 size. Among some of the tribes a single hot stone 

 nearly as big as the head is used, and replaced by 

 smaller ones until the work is completed. Hot sand 

 is .also used in some localities. The lips are then 

 fastened by long pendent cords, and one is run 

 through the top of the head to suspend it. Finally, 

 the cut in the back of the neck is sewn up, and the 

 trophy is completed. Originally a tribal custom of 

 celebrating a victory over an enemy, the Jivaro 

 Indian was not slow to turn it to commercial use 

 when he found that the heads were in great demand 

 among white men. We are told that advance orders 

 were booked and in due course filled 



Dr. Marianne Plehn directs attention in an article 

 in the Allgemeiiie Fischerei-Zeitung for August, a trans- 

 lation of which has been sent to us by the Editor of 

 the Fishing Gazette, to what she regards as a hitherto 

 unrecognised cause of disease in fish kept in tanks and 

 ponds : this is an excessive quantity of oxygen in solu- 

 tion in the water. It is well known that an abundant 

 growth of algae in fish cultural ponds may be very 

 injurious. So much oxygen is given off by the 

 plants that the water may effervesce when it is stirred 

 violently. In such circumstances more of the gas is 

 taken up by the blood of fishes than can be used in 

 the ordinary way by the tissues, and then a further 

 rise in the water temperature may cause the liberation 

 of gaseous oxygen in the blood. Vesicles, visible to 

 the naked eye, are said to form in the skin, par- 

 ticularly on the fins. Siyiilar gas vesicles may form 

 in the orbits, giving rise to "exophthalmos." Gas 

 embolisms may even form in the heart and vessels 

 of the gills, causing immediate death. Not only 

 oxygen, but also nitrogen, may, at times, be con- 

 tained in solution in freshwaters to such an extent 

 as to be the occasion of this " Gaskrankheit," and the 

 author Also suggests that gas-forming bacteria in the 

 blood of fishes may be the cause of similar effects. 

 The matter is one of much importance in salmon and 

 trout hatcheries, and, quite evidently, it should be 

 the subject of very careful investigation. 



A TELEGRAM from Asmara (Eritrea) reports a rather 

 severe earthquake in that region on or shortly before 

 August 15. The shock was especially strong at Mas- 

 sowah and in the surrounding country, at least four 

 people being killed and about twenty injured, while ' 



NO. 2704, VOL. 107] 



several houses collapsed. As a rule the earthquakes 

 of Eritrea are infrequent and of slight intensity. Prof. 

 Palazzo, in his catalogue of Ethiopian earthquakes 

 from 1400 to 1912 (Boll. Soc. Sism. Ital., vol. xix., 

 I9i5» PP- 293-350), records 142 shocks, the strongest 

 of which occurred in 1400, 1884, and 190 1. Asmara 

 itself seems to be one of the least stable regions. 

 Early in 1913 (from January 24 to April 8), 208 dis- 

 turbances were registered at the seismological station 

 in that place, the strongest of which was of about 

 the same intensity as the recent earthquake. 



It is satisfactory to learn that the valuable work 

 of the Kilauea Volcano Observatory is to be main- 

 tained, if not extended. Under the supervision of 

 Dr. T. A. Jagger, jun., and supported by the 

 Hawaian Volcano Research Association, all changes 

 in the activity of the volcano have been chronicled 

 for some years, and the earthquakes, local and other- 

 wise, have been registered. In 1918 a grant of ten 

 thousand dollars was made by Congress, and at the 

 same time the question of placing the observatory 

 under Government direction was considered by a com- 

 mittee of the National Academy of Sciences. On 

 its advice the control of the Kilauea Observatory 

 has been transferred to the Weather Bureau. The 

 full report of the committee has now been published 

 (Proc. Nat. Acad, of Sciences, vol. vi., 1920, 

 pp. 706-16). A general scheme of investigation in 

 either seismology or volcanology is, it considers, be- 

 yond the proper scope of the Weather Bureau. For 

 the present, the committee suggests that seismographs 

 might be added at certain selected meteorological 

 stations, and that such work should, if possible, be 

 placed under the direction of a trained seismcHogist 

 belonging to the Bureau. While the maintenance of 

 the Kilauea Observatory is regarded as of the first im- 

 portance,' the committee recommends that observations 

 should be made on all the active phases of Hawaian 

 volcanism, and that, especially, the gigantic volcano 

 of Mauna Loa, which represents a different stage in 

 the development of a basaltic volcano, should be sub- 

 jected to an investigation as systematic as may be 

 possible, taking into account its much greater size 

 and the difficulty of access. 



The hydrous calcium borate inyoite, described by 

 W. T. Schaller from California in 19 16, has now 

 been found at a second locality, the Whitehead 

 gypsum quarry, Hillsborough, Albert County, New 

 Brunswick. E. Poitevin and H. U. Ellsworth de- 

 scribe a number of crystals, confirming the mono- 

 clinic character of the mineral (Canada Depart, 

 of Mines, Geol. Surv., Bull. 32, 1921). It is "fairly 

 soluble " in water, and separated out somewhat later 

 than the massive gypsum, in the cracks of which it 

 lies. 



The Geological Survey of Ireland has issued through 

 the Ordnance Survey two new sheets of the geological 

 map of the country' on the scale of a quarter of an 

 inch to a mile (i : 253,440). Sheet 5 covers a region 

 of unusual interest, and should be speciallv useful 

 to dwellers in Belfast. Educationally, it serves as 

 an epitome of the geology of Ireland. It includes the 



