Dr. W. Baird on a new Species 0/ Branchipus /rem Jerusalem. 209 



mycelium. The signification of this fact is, at the present time, 

 not understood : it is not known if those varieties in form are 

 produced by variations in the mode of nutrition, and so far 

 referable to those noticed by me as varieties or morbid produc- 

 tions, or if, as is possible, they are organs of dissimilar purpose, 

 belonging to a particular species of Fungi and intended to carry 

 out a sexual conjugation. In this latter case, it might be pre- 

 sumed that Syzygites is the prothallium of a more perfect form 

 of Fungus. 



The result of all these inquiries is, that all known species 

 of plants possess, besides an asexual multiplication of individuals 

 by cell-division or gemmation, a means of preserving the species 

 by sexually developed germs, and that in these special repro- 

 ductive organs a normal germ is never formed without the opera- 

 tion of a fertilizing material, — that, consequently, parthenogenesis 

 never occurs in plants. 



XXI. — Description of a new Species 0/ Branchipus (B. eximius), 

 from the Pool of Gihon in Jerusalem. By W. Baird, M.D., 

 F.L.S. 



[Plate XII.] 



In the f Annals and Magazine of Natural History' for Oct. 1859, 

 I described five new species of Entomostraca, from the Pool of 

 Gihon in Jerusalem. In that paper I mentioned that, in addi- 

 tion to those species forwarded to me alive by my friend Mr. 

 Denny of Leeds, a pair of a species of what I then thought to 

 be a Chirocephalus, from the same habitat, were kindly sent, but 

 that they had died and become decomposed before I had the 

 satisfaction of examining them. Since then, Mr. Denny has 

 forwarded to me several specimens of the same Crustacean, also 

 alive, reared from mud taken from the same pool at Jeru- 

 salem. A careful examination has proved them to belong to the 

 genus Branchipus ; and very elegant and beautiful little creatures 

 they are. In their habits they closely resemble the Chirocephalus 

 diaphanus found in this country, swimming chiefly on their back, 

 and gracefully moving along, their numerous branchial feet 

 being in constant motion. The females had their ovarian sacs 

 full of ova, but they all died before these eggs were hatched. 

 The following is a description of this interesting species : — 



Branchipus eximius. 



Body of a white colour. Tail fully the length of the body, and 

 terminating in two lobes, which are beset with finely plumose 

 seta? on their inner sides only. Outer edge showing a few (about 

 twelve) short teeth near the base. 



Ann. fy Mag. N. Hist. Ser. 3. Vol. viii. 14 



