1890.] The Patterns in Thumb and Finger Marks. 455 



In the young worm which has just escaped from the cocoon, the 

 funnels are ciliated, and they are each of them connected by a short 

 tube, in which a lumen has been developed, but which ends blindly in 

 close proximity to a coil of nephridia. No trace of any nephridial 

 tube other than the sperm duct or oviduct could be observed, whereas, 

 ,in the preceding and succeeding segments the rudimentary nephridiul 

 funnel and a straight tube leading from it direct to the body wall 

 were perfectly plain. Dr. Bcrgh* has figured, in his account of the 

 development of the generative organs of Lumbricus, a nephridial 

 fnniiel in close contact with tlie funnel of the genital duct. It may 

 be suggested that a corresponding funnel has been overlooked in the 

 embryo Acanthodrilus ; the continuity of a structure, identical (at 

 first) with the nephridia of the segments in front and behind, with 

 the genital funnels, seems to show that a search for an additional 

 nephridial funnel would be fruitless. 



I can only explain these facts by the supposition that in Acantho- 

 drilus muitiporus the genital funnels and a portion at least of the ducts 

 are formed out of nephridia. This mode of development is a confirma- 

 tion, to me unexpected, of Balfour's suggestionf that in the Oligochseta 

 the nephridium is broken up into a genital and an excretory portion. 



In tho comparison of the facts, briefly described here, with the 

 apparently independent origin of the generative ducts in other 

 Oligochaeta, it must be borne in mind that in Acanthodrilus the segre- 

 gation of the nephridiurn into several almost detached tracts com- 

 municating with the exterior by their own ducts precedes the 

 formation of the genital ducts. 



II. "The Patterns in Thumb and Finger Marks: on their 

 Arrangement into naturally distinct Classes, the Perma- 

 nence of the Papillary Ridges that make them, and the 

 Resemblance of their Classes to ordinary Genera." By 

 FRANCIS G ALTON, F.R.S. Received November #,.1890. 



(Abstract.) 



The memoir describes the results of a recent inquiry into the 

 patterns formed by the papillary ridges upon the bulbs of the thumbs 

 and fingers of different persons. The points especially dwelt upon in 

 it are the natural classification of the patterns, their permanence 

 throughout life, nnd the apt confirmation they afford of the opinion 

 that the genera of plants and animals may be isolated from one 

 another otherwise than through the influence of natural selection. 



* ' Zeitschr. Wiss. Zool.,' 1886. 



t ' Compar. Knibrjol.,' vol 2, p. 617. 



