Polyphyletic allopolyploid origin ofRanunculus cantoniensis (4x) fromR. silerifolius (2x) ×R. chinensis (2x)

Both diploid and tetraploid experimental interspecific hybrids betweenRanunculus silerifolius (2x) andR. chinensis (2x) exhibit normal bivalent pairing. However, microspores of diploid hybrids do not undergo mitosis and their pollen grains are highly sterile, whereas tetraploid hybrids form good pollen grains after microspore division. Evidence is forwarded for the assumption thatR. cantoniensis (4x) has originated by hybridization between these two diploid parental species and by polyploidization of the diploid hybrids. Parallelisms between the different karyotypes ofR. cantoniensis (4x) andR. silerifolius (2x) suggest that the former is a species of polyphyletic origin.     

Studien überAcanthodes. 4.Acanthodes boyi n. sp., die dritte Art der Acanthodier (Acanthodii: Pisces) aus dem Rotliegend (Unterperm) des Saar-Nahe-Beckens (SW-Deutschland)

WithAcanthodes boyi n. sp. another new species of acanthodians from the Saar - Nahe -Basin is described. Only the holotype is known. The specimen differs in several characteristics such as stages of ossification, vertebral column, development of the shoulder girdle, development of the fin spines, and other details from both known species,Acanthodes bronni (Agassiz) andAcanthodes tholeyi (Heidtke).