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of a lime-secreting, sparsely branched marine alga in which the 

 thallus or stem is not at first divided by transverse septa. All 

 of the original softer parts of the alga, filaments or stems, 

 branches and algal cells, have evidently either been replaced, 

 or incrusted, by calcareous matter. The algae, or their frag- 

 ments, together with macerated shell matter, containing crinoid 

 stem joints and numerous bryozoan remains, now constituting 

 Salem limestone, were apparently deposited on shallow shores. 

 (See literature cited by Professor Robert R. Shrock (1).) 



My attention was first directed in 1934 to these fossils, 

 which were at that time locally known as "vertebral back 

 bones," and then, late in 1935, to the article written by Pro- 

 fessor Shrock entitled : "Probable Worm Castings ('Coprolites') 

 in the Salem limestone of Indiana" and included in "Inverte- 

 brate Paleontology" by Twenhofel and Shrock (2). 



These authors received my evidence as to the algal nature 

 of these fossils late in 1935 and in 1937 (see literature, note 3), 

 and my suggestion that they be referred to the lime-secreting 

 Polysiphonia, which, however, are of relatively very small size, 

 and much branched forms. I now believe that Cymopolia (fam. 

 Siphoneae, which includes Diplopora, Gyroporella and Dactylo- 

 pora) is the genus nearest to Glohulinea, as illustrated in Fig. 

 509 of Haas: "Die Leitfossilien," but which former is distin- 

 guished from the new genus by its numerous whorled, bifurcat- 

 ing or compound branches, lack of a stem sheath, relatively 

 minute size, and much more recent geological age. 



My reasons for favoring algal, and not annelid origin, for 

 these fossils in short are the following : 1 . Where best developed 

 the markings almost always lie flat and parallel to the stone 

 bedding planes, and not transverse thereto. 2. The material 

 inside the stalks (or rods) and beads is essentially like the sur- 

 rounding granular limestone. 3. Stalks and beads alike are 

 separated from the surrounding rock by a tiny groove, suggest- 

 ing that there was once some sort of a cell wall around them. 

 4. In some instances the "rods" bend back at an acute angle, 

 in a bend which a worm could hardly make. 5. Some of the 

 stalks fork, or branch, as in the var. catenaeforniis , such normal 

 power of branching being unique among the worms, and as 

 far as I know, only observed in the tiny annelid Syllis ramosa, 

 found living in "glass sponges" in Eastern seas. 6. Small lobate, 



