December 6, 1895.] 



SCIENCE. 



749 



among the most primitive and generalized 

 of Coleoptera, and that from work based on 

 such studies as these of the life-history of 

 this and allied groups there has already re- 

 sulted the germs of a truer phylogeny or 

 classification of the entire order of Coleop- 

 tera. Of similar import are Eiley's papers 

 on the larval habits of bee-flies, on the 

 luminous larviform females of the Phengo- 

 dini and on the first larval stage of the 

 pea-weevil (Bruchus). His studies on the 

 systematic relations of Platypsyllus as de- 

 termined by the larva evince his patience, 

 accuracj^ and keenness in observation and 

 Ms philosophic breadth. 



For over twenty years he made observa- 

 tions on the fertilization of Yucca by those 

 remarkable tineoid moths, Pronuba and 

 Prodoxus, and from time to time published 

 papers and notices of progress in his work 

 which culminated in his paper entitled ' The 

 Yucca Moth and Yucca Pollination ' (1891- 

 '92), a memoir remarkable for the patient, 

 unremitting work carried on during his 

 spare hours, its thoroughness in dealing 

 with structural details, its critical accuracy, 

 and for its faithful and artistic drawings. 

 It is a paper of interest to botanists as well 

 as zoologists, and of value to the student of 

 evolution. One of his last papers was a 

 continuation and resume of this subject en- 

 titled ' Some Interrelations of Plants and 

 Insects' (1892). 



Riley's contributions to the history and 

 structure of the Phylloxera, of the scale in- 

 sects, of the hop-plant louse, the Pemphigi- 

 nse, Psyllidse, etc., are of permanent inter- 

 est and value. His best anatomical and 

 morphological work is displayed in his 

 study on the mode of pupation of butter- 

 flies, the research being a difficult one, and 

 especially related to the origin of the cre- 

 master, and of the vestigial structures, sex- 

 ual and others, of the end of the pupa. 

 Whatever he did in entomology was orig- 

 inal. He may occasionally have received 



and adopted hints and suggestions from his 

 assistants, but he laid out the plan of work, 

 supervised every detail, followed up the 

 subject from one year to another, and made 

 the whole his own. His originality in a 

 quite different direction from biology is seen 

 in his paper entitled ' Perfectionnement 

 du Grraphophone,' read befoi-e the French 

 Academy of Sciences at Paris, in 1889. He 

 was also much interested in Aeronautics, 

 and took much delight in attending seances 

 of spiritualists and exposing their frauds, 

 in one case, at least, where another biolo- 

 gist of world-wide fame, then visitiug in 

 Washington, was completely deluded. 



Riley was from the first a pronounced 

 evolutionist. His philosophic breadth and 

 his thoughtful nature and grasp of the 

 higher truths of biology is well brought 

 out in his address on ' The Causes of 

 Variation in Organic Forms,' as Vice- 

 President, before the biological section 

 of the American Association for the Ad- 

 vancement of Science in 1888. He was a 

 moderate Darwinian, and leaned, like other 

 American naturalists, rather to Neo-La- 

 marckism. He saj's: " I have always had a 

 feeling, and it grows on me with increasing 

 expei'ience that the weak features of Dar- 

 winism and, hence, of natural selection, are 

 his insistence (1) on the necessity of slight 

 modification; (2) on the length of time re- 

 quired for the accumulation of modifica- 

 tions, and (3) on the absolute utility of the 

 modified structure." Riley from his ex- 

 tended experience as a biologist was led to 

 ascribe much influence to the agency of ex- 

 ternal conditions, remarking, in his address: 

 " Indeed, no one can well study organic 

 life, especially in its lower manifestations, 

 without being impressed with the great 

 power of the environment." He thus con- 

 trasts Darwinism and Lamarckism : " Dar- 

 winism assumes essential ignorance of the 

 causes of variation and is based on the in- 

 herent tendency thereto in the oflspring. 



