318 Mr. A. Tulk on the Anatomy 0/ Phalangium Opilio. 



tomy of the inflorescence in F. olitoria is usually (invariably ?) 

 repeated four times ; it would be desirable therefore to ascertain 

 if there be any regularity in the number of divisions in the in- 

 florescence of the other species. 



In connexion with this subject^ I cannot omit stating my be- 

 lief, that British botanists have paid too little attention to the 

 order of expansion of the flowers of our native plants. 



The important inferences which may be deduced from obser- 

 vations on this subject were long ago pointed out by Mr. Brown, 

 in a paper in the twelfth volume of the ' Transactions of the Lin- 

 naean Society.^ 



XL. — Upon the Anatomy 0/ Phalangium Opilio {Latr.). 

 By Alfred Tulk, M.B.C.S., M.E.S. 



[Concluded from p. 253.] 



[With a Plate.] 



The female organs of generation occupy a similar position within 

 the abdomen to those of the male, and are composed of the fol- 

 lowing parts, viz. an ovipositor contained like the penis within a 

 sheath, and an ovisac and ovarium. 



The ovarium (PI. V. fig. 26. 0) is a white, dehcate and trans- 

 parent membranous tube traversing the whole circumference of , 

 the ventral aspect of the abdomen, and returning into itself an- \ 

 teriorly at a point (0^) where it opens into the ovisac. It is in 

 relation above, with the under surface of the digestive sac and fatty 

 mass ; beneath, with the terminal portions of the ovipositor, the 

 oviduct and abdominal nervous ganglia ; while upon either side 

 it dips deeply down under the coxae of the posterior pair of legs, 

 where the two tracheal trunks pass over it near to their origin. 

 The anterior half of this tube (0^) is narrow, and it widens out 

 gradually behind for the remainder of its extent, to contain a 

 great number of ova in difi*erent stages of their development, from 

 the size of a small pin's head to those which are scarcely visible 

 to the naked eye. I have constantly observed that the largest or 

 most advanced ova were situated in that part of the ovarium near- 

 est to the ovisac, or most internally (PI. V. fig. 27.). Each ovum 

 is retained in a separate csecal pouch of the ovarium, which sur- 

 rounds it closely, and can be seen only upon rupturing it and 

 allowing the ovum to escape. I have never met with ova in the 

 anterior part of the ovarium, which contained instead irregular 

 patches of an opake granular matter. 



The next organ, the ovisac (PI. V. figs. 26 and 27. U), occu- 

 pies the space included within the inner circumference of the 

 ovary, being in contact superiorly with the fatty mass, and crossed 



