Miscellaneous. 391 



stase), and partly into gaseous compounds decomposed by contact 

 with the air into carbonic acid and these ammoniacal derivatives. 



The sui-prising circumstance that the plant should in this way 

 give off as an excretion a part of its scanty supply of nitrogen loses 

 its improbability, as the author remarks, when we know that the 

 tips of the roots usually have an acid reaction, and that the ammo- 

 niacal derivatives carried down by water into the soil are again 

 taken up by them. 



Karsten expresses a hope that a thorough study of these conditions 

 will elucidate many phenomena which are still obsciu'e and inexpli- 

 cable, — for example, the penetration of many gei-minating parasitic 

 fungi into particular organs of plants, particularly such as the de- 

 veloping embryos of more highly organized plants, and their leaf- 

 and flower-buds — and the finding of the fissures of these organs by 

 the germinal mycelium of the fungus, which not unfrequently 

 takes place — further, the finding of the micropyle of atropal ovules 

 projecting freely into the cavity of the ovary by the pollen-tube ; for 

 probably each of these organs exhales a specifically jieculiar compound 

 which serves as the first nourishment of some one definite kind of 

 growing fungal germ or pollen-tube, and guides it to the place of 

 its subsequent development. — Zeitschr. des allgem. 'osterr. Ajjotheker- 

 Vereines, No. 11, 1871. Communicated by the Author. 



A new Genus of the Eolididae. By Prof. Salvatore Trijtchese. 



Prof. Trinchese, of Genoa, has described a new form belonging to 

 the family Eolididae, obtained upon seaweeds in the port of Genoa, 

 in May 1869. He regards it as forming a new genus most nearly 

 aUied to Hermcea, Loven, but also presenting considerable affinity 

 to the genera Phyllohranchus, Bergh, and Chiorcera, Gould. He 

 characterizes it as follows, under the name of 



Beccaeia. 



Corpus elongatum, subcompressum, postice attenuatum. Caput di- 

 stinctum, utrinque in lobum planum extensum. Poclarium latum, 

 angulis anterioribus acutis, paullulum productis. Branchim 

 numerosae, foliaceae, seriebus minus distinctis ad latera dorsi 

 dispositae. RMnophoria (superior tentacles) longa, foliacea, eon- 

 voluta. Foramina generationis {et anil) ad dextrum latus. 

 MaxillcB nullse. Radula dentibus validis non denticulatis pra- 

 dita. 



The genus is named in honour of Prof. Beccari. 

 For the species he proposes the name of Beccaria tricolor ; it is of 

 a delicate green colour throughout, but covered with small globules 

 of a splendid white and deep carmine-red colour. These extend 

 also to the tentacles and branchial leaves. The white globules form 

 a transverse band across the anterior margin of the body and an- 

 other immediately in front of the pericardial sac. On the dorsal 

 surface of the latter they are arranged in little round groups cir- 

 cumscribed and separated by red globules ; and a similar arrange- 



