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SCIENCE 



[N. S. Vol. XXXIX. No. 1001 



customs and ideas of to-day have roots in the 

 past which are hardly suspected by the gen- 

 eral public. On the whole, the book makes 

 melancholy reading, unless one can enjoy the 

 contrast between ancient follies and our own 

 astonishing superiority! The study of past 

 error and confusion is certainly of value as 

 exhibiting the weak spots in our social organ- 

 ism, and enabling us to be on our guard 

 against early symptoms of decay in the soci- 

 eties to which we belong. Thus, the author 

 says: 



" If one attempt to scan the field of the 

 history of medicine, to take note of all the 

 fallacies and superstitions which have be- 

 fogged men's minds, and brought about what 

 now seem to be the most absurd and revolting 

 views and practises of times gone by, and if 

 one search deliberately for that which is of 

 curious nature, or calculated to serve as a 

 riddle difficult of solution, he will scarcely in 

 the tomes which he may consult find anything 

 stranger than the close connection, nay, even 

 the identity maintained for centuries, between 

 the trade of the barber and the craft of the 

 surgeon. Even after having studied history 

 and the various laws passed at different times, 

 he will still miss the predominant yet con- 

 cealed reason for this state of affairs. This 

 will be found to be, in the words of Paget, the 

 ' maintenance of vested rights as if they were 

 better than the promotion of knowledge.' " 



It is impossible to contemplate this history 

 without asking whether to-day the " concealed 

 reason " mentioned by Paget is not still power- 

 ful, and serving to prevent our academic insti- 

 tutions from readily adapting themselves to 

 their social environment. From another point 

 of view doubt may be expressed as to the com- 

 plete validity of the author's historical method. 

 Prom time to time we find fault with the pro- 

 fessional historian, who, depending on docu- 

 mentary evidence, seems to over-emphasize the 

 miseries and stupidities of former days. We 

 like better our Morris and Scott, who offer 

 us pictures of moving life, full of romance, 

 adventure and high ideals. It is easy to 

 criticize such writings, as we criticize the 

 landscape artist who makes idyllic pictures of 



suburban lanes, leaving out the tin cans, dead 

 cats and evil smells. Yet after all, life was 

 life in those days, and the best that is in us 

 calls across the ages to the best that equally 

 existed in our ancestors. Dr. Park's accounts 

 may be true as to facts, and yet to some ex- 

 tent misleading to those who have not other 

 sources of information. 



T. D. A. COOKEEELL 



BEETLES BECOMING PAZASITES 

 In all the great group of beetles, 50,000 

 species strong, and of an extraordinary vari- 

 ety of external appearance and of habit, wit- 

 nessing to a ready plasticity and adaptiveness, 

 there are but few indications of a resort to 

 parasitism as a shift for a living. The Sty- 

 lopidsg, it is true, are parasites (in the bodies 

 of wasps, bees and leaf hoppers), but these 

 insects are no longer considered to be aber- 

 rant beetles, but to constitute a quite dis- 

 tinct order, more nearly allied to the Hymen- 

 optera or Diptera than to the Coleoptera. 



The classic and single conspicuous example 

 of a parasitic beetle, living all of its life (both 

 larval and adult) on its host, is the well- 

 known beaver parasite, Platypsylla castoris, 

 common both in Europe and America. This 

 insect lives as an external parasite among the 

 hairs on the outside of the host's body, and 

 feeds on the hairs and dermal scales, just as 

 the Mallophaga (biting bird lice), of birds 

 and manunals, do. It has a highly modified 

 body, and is the only species of its genus and 

 family. 



Another small beetle, however, Leptinus 

 testaceus, of the family Leptinidse, is known 

 in both Europe and America as a frequenter 

 of the nests of field mice, shrews and other 

 small mammals of similar habit. It has also 

 been taken from bumble bees' nests. I have 

 recently received several specimens of this 

 beetle which were taken from the bodies of 

 freshly killed shrews on Forrester Island, 

 Alaska, by Professor Harold Heath. The 

 beetle's body is not modified (by flattening, 

 fusion of thoracic segments, etc.) in any such 

 extreme way as is that of Platypsylla or the 

 Mallophaga, but it shows, nevertheless, the 



