HISTORY OF RESEARCH. xxxiii 



Gephalograptus, Hopkinson); and (11) D. t&retiusculus. Geinitz regards the three 

 Graptolite forms D. secalinus, D. laxus, and l>. distichus as doubtful species. 



His genus Cladograpsus is divided by him into two groups, for which, however, 

 he did not suggest sub-generic titles. Those constituting his first group (a) are at 

 present united in the genus Dicranograptus, Hall ; those in his second group (l>) are 

 divided between Dicellograptus, Hopk., and Didymograptus, Hall. His first group 

 contained Hall's species of (12) Gladograptus ramosus and (13) G. furcatus. In 

 the second group are included a new species, ( I 1) < '. Forchammeri, and the previously 

 described forms (15) C. Murchisoni, (16) G. serra, (\7) G. sextans, and (18) G. 

 serratulus. 



Under Monograpsus the following are figured and described : — (19) Monograpsus 

 Sagittarius, (20) iff. Barrandei, (21) M. nuntius (under this name are included 

 some scalariform views of a Glimacograptus), (22) M. tectus, (23) M. NUssoni, 

 (24) M. bohemicus, (25) M. incisus, (26) M. virgulatus, (27) M. colonus, (28) 

 M. latus ( = M. Boemeri), (29) M. chimgera, (30) M. testis, (31) ,1/. SedgwicJcii, 

 (32) M. Halli, (33) M. distans, (34) M. Becki, (35) M. JV«i, (36) 71/. ^Wo», 

 (37) iff. millepeda, (38) If. proteus, (39) ilf. convolutus, (40) ill. turHculaUs, 

 (41) ill. triangulatus, (42) ilf. gemmatus, (43) M. peregrinus, (44) Af. IAnnsei, and 

 two new forms, (45) If. Heubneri and (46) ,17. Salteri. 



Geinitz enters fully into the discussion of the structure of Retiolites, and gives 

 his support to the views of Barrande rather than to those of Suess. 



Distribution . — An important section of Geinitz's work is devoted to the general 

 distribution and range of the Graptolites, but little or no advance is made on the 

 facts and conclusions previously given by Barrande and others. 



A short paper by Salter appeared in the same year. In 

 ct a u er this a few species of Graptolites obtained by Harkness Prom 



" Description of some the South of Scotland are figured and described. Under 

 Graptolites from the the name (1) D. teretiusculus, some specimens of Glimaco- 

 Silunau of Scotland," graptus are figured, one of these being certainly referable to 

 'Quart, Journ. Geol. Q 8charen i ergi (Lai)w.) ; (2) Gr. Flemingii is described as a 



Soc ,' vol. viii. . \ . . n 



new species, and a form referred to (3) Gr. Sagittarius is 



figured; but Gr. laxus, Gr. Nicoli and Gr. taenia, Salter, are not considered by the 

 writer to be distinct species. 



As regards the range of the Graptolites, Salter says that " there is no evidence 

 of a double Graptolite being found above the Oaradoc Sandstone" ("Llan- 

 dovery " of modern geologists). 



Hall, in the second volume of his ' Palaeontology of New 

 York,' figures and describes the two species (1) Gr. clinto- 



lT , , , , . . T nensis and (2) Gr. venosus from tin' Clinton beds, previously 



Jralseontologv or New v / r J 



York,' vol. li. named by him in 1843 and L849. The former is a Mono- 



graptus, allied to M. riccartonensis, the latter a Retiolites, 



