380 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Origin of Vasa efferentia in Tortoises.* — Herr Friedrich von 
Molier, in the course of some observations on the urinogenital system of 
tortoises, examined two young males of Emys lutaria and Clemmys leprosa 
respectively 2*5 cm. and 4*9 cm. in length, and found that in neither 
was there any connection between testes and Wolffian ducts. He found 
a series of canals which are the future vasa efferentia , but which arise 
neither from the testes nor from the kidneys, but, as he believes, from 
the peritoneal epithelium. This result is very different from those of 
most observers on Amniota, who describe the vasa efferentia as arising 
from the genital ridge (Semon, Braun, Hoffmann), or from the kidney 
(Schmiegelow, von Mihalkovics) ; but it agrees with Semper’ s results for 
Selachians; for the latter describes the vasa efferentia as arising there 
from the nephrostomes which originate from the peritoneal epithe- 
lium. 
Lorenzini’s Ampullae in Acanthias vulgaris, f — Herr GostaForssell 
has employed modern histological methods in the investigation of the 
structure of the sensory ampullm of this dog-fish. In regard to the 
gross anatomy, reconstructions from serial sections showed that the 
inner end of the ampulla divides up into a number of fine tubes, which 
are furnished with numerous (18-31) finger-shaped diverticula. Histo- 
logically the diverticula differ markedly in structure from the canal 
proper. The former are lined by an epithelium composed of two kinds 
of cells: — (1) supporting cells which anastomose to form a “ basketwork ” 
round (2) large pear-shaped cells apparently in close connection with 
nerve-fibrils. The ampullar canal itself is lined by very peculiar cells, 
each of which has projecting from its inner surface a long columnar pro- 
cess with a reticular structure, the meshes of the reticulum in life being 
apparently filled with a semi-fluid substance. These processes project 
into the lumen of the canal, tend to fuse together, and thus form the 
gelatinous mass which fills the cavity of the ampulla. The author be- 
lieves that the ampullae as a whole are sense-organs, and that the gelatin- 
ous contents serve to propagate the sense impressions to the sensory cells 
of the diverticula, and also to protect those cells from injury. The 
research being solely histological casts no light on the special nature of 
the sense involved. 
Reproductive or Genetic Selection.^ — Prof. Karl Pearson uses this 
term to describe the selection of predominant types owing to the differ- 
ent grades of reproductivity being inherited, and without the influence 
of a differential death-rate. 
The problem whether fertility is or is not inherited is one of far- 
reaching consequences. That fertility should be inherited is not consist- 
ent with the organic stability of a community of individuals, unless 
there be a differential death-rate, more intense for the offspring of the 
more fertile ; i.e. unless natural selection or some other factor holds 
reproductive selection in check. The inheritance of fertility, and the 
correlation of fertility with other characters, are principles momentous 
in their results for our conceptions of evolution ; they mark a continual 
* Zeitschr. f. wiss. Zoo!., lxvi. (1899) pp. 573-98 (3 pis.). 
t Op. cit., lxv. (1899) pp. 725-44 (l pi.). 
X Proc. Koy. Soc., lxiv. (1899) pp. 163-7 
