610 



SCIENCE 



[N. S. Vol. XL. No. 1034 



dicating somewhat its noxious effects. Some- 

 times it is also called " ctichicaste." 



The stinging hairs of Jatropha urens show 

 the same structure as those of the common 

 nettle (Urticacese), though the two plants be- 

 long to different families. The poison is pro- 

 duced by a cell of the epidermis which, during 

 the growth, swells up, forming a goblet- 

 shaped bulb, set into the surrounding tissue. 

 The hair then represents a long tube, the walls 

 of which have incrustations of silicic acid in 

 the upper part and are calcified in the lower 

 parts, so that they are very brittle and break 

 at the lightest touch. Near the top this cell 

 expands a little, in the form of a miniature hat 

 with very thin walls, so that when touched, it 

 breaks in an oblique direction, forming the 

 point of a cannula, which enters the skin of 

 animal or man. At the same time the poison- 

 ous liquid of the cell is discharged into the 

 wound, and produces instantly a local in- 

 flammation. The mechanism is, in fact, the 

 same as that of the poison fang of the snakes, 

 and it is also similar to the cannula of the 

 surgeon. 



To estimate the formidable effects of the 

 hair and the intensity of its poisonous liquids, 

 it has been calculated that about 10,000 hairs 

 of the common nettle may produce one drop of 

 poison (0.05 c.cm.). As in the ease I am going 

 to mention, about 10 hairs of the Jatropha 

 were broken. It may be calculated on the same 

 basis that about 0.00005 c.cm. of poison en- 

 tered the wound. This is, however, a low esti- 

 mate, because the hairs of our plant and their 

 inner cavity are larger than those of the com- 

 mon nettle and the amount of poison intro- 

 duced into the system in the following occur- 

 rence was probably much larger than it would 

 have been in the case of an equal contact with 

 Urtica urens. 



On an excursion 'along the San Felix River, 

 in eastern Chiriqui, with Dr. MacDonald, 

 geologist of the Canal Commission, the writer 

 became acquainted with Jatropha urens by 

 unavoidable contact with a single specimen 

 of the plant. All at once he felt an intense 

 burning on the left hand, where about 10 of 

 the stinging hairs had entered pretty deep into 



the skin. The inflammation produced by this 

 touch was very similar to that produced by 

 nettles, but the pain soon increased, the whole 

 hand began to swell and inside of half an hour 

 had assumed a monstrous shape. Then the 

 arm commenced to swell also, the right hand 

 and arm, without having been innoculated, yet 

 showed the same abnormal symptoms, and a 

 very strong itching sensation was felt all over 

 the upper part of the body. At about the same 

 time parts of the face, around the eyes and 

 nose, swelled considerably. The itching sen- 

 sation rapidly spread over the abdomen and 

 the lower extremities and red pimples ap- 

 peared everywhere. In less than an hour the 

 poison had extended over the whole surface of 

 the body, and its entrance into the blood cur- 

 rent was indicated by the corresponding physi- 

 ological reaction of the interior organs. The 

 palpitation of the heart became extremely 

 accelerated and the mind was soon overcome 

 by an agonizing depression. The respiration 

 seemed to be delayed as if under a great pres- 

 sure, cold sweat broke out, and the patient gave 

 way altogether, remaining unconscious for 

 more than an hour, except for feverish 

 dreams. After coming back to his senses, he 

 had several fits of copious vomiting, from 

 which it may be surmised that the poison was 

 slowly eliminated from the organism. The 

 weakness, however, remained for several days. 



A case of such extreme effects, which might 

 have killed a man of less strength than the 

 writer, has never been recorded, as far as the 

 literature on the subject shows. Undoubtedly 

 the intensity of the intoxication was due to 

 the rather strong contact with the plant, which 

 caused a considerable amount of poison to be 

 introduced into the blood circulation. 



Many other tropical plants, among them 

 some Urticaceae and Loasacece, have such 

 deadly stinging hairs, the poison of which is 

 active enough to kill a man, even in a rela- 

 tively small dose. The only way of allaying 

 its effects would be to neutralize or precipitate 

 it by means of a prompt application of chloride 

 of lime, ammonia or sodium permanganate. 



Otto Lutz 



INSTITUTO NACIONAL DE PANAMA, 



Panama, E. de P. 



