178 



results are the restriction of the generic name Sphaerosoma to 

 two (or three?) already published European and American species 

 and the description of the Californian plant as Ruhlandiella 

 hesperia sp. nov. 



Dr. N. L. Gardner's paper on "Variations in nuclear extrusion 

 among the Fucaceae" sets forth the results of a study of the 

 formation of the oospheres in the commoner Californian repre- 

 sentatives of the rockweed family. Decaisne and Thuret, in a 

 paper published in 1845, were pioneers in a comparative study 

 of the number of oospheres to an oogonium in the Fucaceae* 

 and as one of the results of their researches defined four genera 

 having their respective numbers of oospheres in a beautiful 

 geometrical series: Cymaduse (^ Bifurcaria) with one oosphere 

 to the oogonium, Pelvetia with two, Ozothallia (= Ascophyllum) 

 with four, and Fucus with eight. Gardner finds that some of 

 the Californian Fucaceae do not fit into this scheme very well. 

 In the plant that has been known as Fucus Harveyanus eight 

 nuclei are formed by divisions of the original oogonium nucleus, 

 but only two oospheres are developed ; these are of very unequal 

 size, the larger containing a single large nucleus and the smaller 

 seven small nuclei. It is presumed that only the larger oosphere 

 is capable of fertilization. Chiefly on these grounds, Fucus 

 Harveyanus is considered the type of a new genus Hesperophycus 

 Setchell & Gardner. In a somewhat similar way, while the 

 typical Pelvetia fastigiata of California agrees essentially with the 

 European Pelvetia canaliculata in forming two practically equal 

 oospheres to an oogonium, the plant that has been known as 

 Pelvetia fastigiata forma limitata Setchell produces two very un- 

 equal oospheres, which had led to assigning it to a new genus 

 Pelvetiopsis Gardner. These results suggest to the reviewer the 

 possibility that similar accurate investigations of the number 

 and character of the oospheres of the remaining Fucaceae of the 

 world might lead to discovery of grounds for several other similar 

 generic segregations and that a large number of genera thus 

 based might prove rather impracticable and unnatural. But 

 there is scarcely more ground for disputing about genera than 

 about tastes and it would certainly be premature to venture any 



