STRUCTURE AND ECONOMY OF SPIDERS. 331 
6. A supernumerary eye, situated between the two 
small ones constituting the anterior intermediate 
pair, has been observed in an adult female Theridion 
jilipes. The total number of eyes possessed by this 
individual was nine, and their arrangement was sym- 
metrical. 
7. The right intermediate eye of the posterior 
row in an adult female Zpetra inclinata had not 
one eighth of the natural size, being merely: rudi- 
mentary. 
8. A short but perfectly formed supernumerary 
tarsus, connected with the base of the tarsal joint 
of the right posterior leg on its outer side, has been 
noticed in an adult female Zycosa campestris. 
9. An adult Pholcus Lyoni presented the remark- 
able fact of the union of the two sexes in the same 
individual, the left side being that of a male and the 
right side that of a female (see-the ‘Annals and 
Magazine of Natural History,’ 3rd series, vol. xix. 
p- 392). 
The particulars stated in the foregoing cases, which 
serve to establish the fact that spiders, in common 
with many other animals, occasionally exhibit in- 
stances of anomalous structure, derive no small de- 
gree of interest from their novelty; but when it is 
borne in mind that all the examples except two have 
reference to those important organs the eyes (impor- 
tant not only as regards the function they perform, 
