128 Rerieics — Dr. G. Holm — On Litiiites. 



III. — Om mynningen hos Lituites, Breyn. Af Gerhard Holm. 

 Geol. Foren, Forhancll. No. 140, Bd. 13, Haft 7, 1891. 



On the Aperture in the gknus Lituitks, Breyn. By Gerhari> 

 Holm. Transactions of the Geological Society in Stockholm, 

 Vol. 13, pp. 736-780, Pis. 10-12. 



THE terminal aperture of the shell in the Lower Silurian Cepha- 

 lopod genus Lituites, Breyn, is so seldom jDreserved intact, that 

 different views have been maintained respecting its true form. 

 Quenstedt stated that it was furnished on the ventral side with two 

 projecting straight lobes. Noetling showed later that there were 

 four of these lobes, one pair on the ventral and the other on the 

 dorsal side ; but in the lately published Brit. Mus. Cat, of the 

 Cephalopoda, A. H. Foord adopts the statements and figures of 

 Lessen that not more than two incurved lobes are present, and 

 considers Noetling's observations erroneous. Dr. Holm has obtained 

 some very perfect individuals both of Lituites lituus, Montf., anel 

 L. tenuicaidis, Kem., which show clearly that in the aperture of these 

 species, there is, in addition to the two pairs of lobes described by 

 Noetling, another small unpaired lobe on the dorsal side, so that, 

 when complete, there are five lobes. This number seems to prevail 

 in the majority of the species, but the author describes a new form, 

 L. discors, in which only three lobes are present, and another, 

 L. pracnrrens, which may possibly only have possessed two lobes, 

 and on account of its strongly marked conical form would come into 

 the so-called genus Ancistroccras. 



A new species of CycIoUtuites, Remele, is also described, which 

 definitely shows that the forms placed in this genus are not merely 

 the loose spirals of species of Lituites, but distinct members of the 

 Lituitidaj family, from which probably the typical Lituites have been 

 developed. G. J. H. 



IV. — The Fossil Insects of North America, with Notes on 

 SOME European Species. By Samuel H. Soudder. Vol. I. 

 The Pretertiary Insects, with Thirty-five Plates. 4to. pp. 456. 

 Vol. II. The Tertiary Insects of North America. 4to. pp. 734, 

 with Twenty-eight Plates.i New York : Macmillan & Co. (1891). 



THE Essays contained in the first volume of the present work 

 have (the author tells us) no logical connection. They were 

 written and printed at different times during the past twenty-five 

 years, and are here issued exactly as first printed. But they cover 

 nearly the whole of a single limited field in palaeontology, of which 

 the author may be said to be almost the sole exponent in America. 

 Mr. Scudder's name is now as familiar to European Palaeontologists 

 as it is to those of America, and, so long ago as 1868, he communi- 

 cated to the Geological Magazine, at the request of Sir Charles 

 Lyell, a most valuable digest " On the Fossil Insects of North 

 America," so far as then known (Geol. Mag. Vol. V. pp. 172-177, 

 and pp. 216-222). 



1 For a Review of vol. ii., sec Geol. Mag. 1891, Decade III. Vol. VIII. 

 pp. 280-282. 



