J. G. WALLER ON PARASITIC VEGETABLE ORGANISMS. 351 



arms, we find a swelling (b), bag like yet definite, a sporangium 

 winch at once allies it to the Saprolegnia or Achlya, amongst which 

 Prof. Duncan placed the parasitic forms he found in fossils, and in 

 which also the above described examples must be placed. There 

 is yet another form of great simplicity, which evidently belongs to 

 this class, PI. XV., Fig. 9, wherein the tube is also regular, of equal 

 diameter, and similar to the last in its measure. But it proceeds in 

 a series of curves, occurring in rhythmical regularity, each having an 

 aperture to the surface. Of all the forms it is the most simple, and 

 it was in a fragment of oyster-shell from the Varne Sand, the others 

 being from the Outer Gabbard. 



Another variety, very similar to Fig. 1., PI. XIV., but perhaps with 

 more regular excavations, is seen in Fig. 2, but is distinguished by 

 its villous character, the whole surface having short bristles (Fig. 3). 

 The diameter of the tube is about the Gf)6th of an inch. In this the 

 warm brown plasmic matter is well seen, and some globular bodies 

 are visible (Fig. 3), but not very easily made out, on account of the 

 dense medium interposing. At Fig. 4, however, globose forms are 

 well pronounced, but they belong to that shown in Fig. 1, and are 

 similar to what some writers have called gonidia. Extremely minute 

 granular objects are also occasionally seen, as in Saprolegnia ferax, 

 Achlya prolifera, &c.,* showing very distinctly the alliance. 



The above-named genera, so close to each other, have hitherto 

 stood on debatable ground, whether to be placed amongst the Alga3 or 

 Fungi ; but which the general feeling amongst eminent naturalists 

 would now assign to the latter. My own opinion in such a matter 

 would be of no value ; all I can say is, that the arguments adduced 

 by those workers who take this view, appear to me to be sound, if 

 not conclusive. The next example is the most remarkable of the 

 objects under consideration. 



If one were to describe this according to its general appearance, 

 it would be as a confused medley of root-like fibres, or filaments, un- 

 symmetrical, contorted, and with every variety of form. This, 

 though roughly giving an idea, would be useless for any scientific 

 purpose ; for sometimes this becomes exceedingly intricate, and 

 developed to such a degree, that the calcareous particle is completely 

 occupied, and presents itself as a dark mass, scarcely distinguishing 

 any organization. At all times a delicate mycelium is seen pervading 



* See "Intellectual Observer," Vol. v., " On Egg Tarasites," by the Eev. 

 JL J. Berkeley, Figs. 2, 10. 



