88 Correspondence — Dr. Gerhard Holm — Mr. H. W. Monchton. 

 cos-ie-iHisi^oisriDEisroiH] - 



" STEM-OSSICLES " OF CRINOIDEA, IN THE LEPT^NA-KALK 

 (UPPER ORDOVICIAN) DALECARLIA, SWEDEN. 

 Sir, — A reviewer (F.A.B.) of my notice "Om forekomaten af en 

 Caryocrinus i Sverige " has said in the Geological Magazine, 

 December, 1890, p. 570 : " The rock is filled with stem-ossicles 

 which Dr. Holm, after the curious custom of collectors, thinks it 

 necessary to ascribe to Crinoidea." What I regard as stems of at 

 least two species of Crinoids, the reviewer says are stems of Cystidea 

 without his having seen a single one of them. But the real fact is 

 that these stems in consequence of their structure must have 

 belonged to Crinoids. One of the supposed species has left frag- 

 ments of stems 45 mm. in length by 16 mm. in breadth. These 

 show the starting-points where strong cirrhi originated, and as 

 far as known cirrhi have not been found in the Cystidea. Thick 

 and expanded rootlets of Crinoids are also not rare. To this must 

 be added, that all known Cystidea from this same locality, with 

 the exception of Caryocrinus cfr ornatus, Say, are devoid of a stem. 

 According to Angelin the genera Sphoeronis, Eucystis and Caryocystis 

 are sessile, having the basis of the perisome itself directly affixed to 

 foreign bodies without the mediation of a stem, and several of the 

 specimens observed by me of Sphceronis oblonga, Aug., and Eucystis 

 sp., either show the surface by which they were attached, or are 

 even yet affixed to Bryozoans or other marine Silurian fossils. Of 

 Caryocystis I have seen only a single specimen, and this does not 

 show the basis of the jDerisome clearly. A species of Eucystis is 

 numericall}' by far the most predominant form. This is the cause 

 why I have, with full intention, referred the stems to Crinoids. 



'"sTS.,, .89.. Gekhaei, Holm. 



THE DENUDATION AND ELEVATION OF THE WEALD. 



Sir, — In the December Number of the Geological Magazine, 

 Dr. Irving states that in my sketch in the September Number 

 I reproduced partly some arguments which he put before the 

 Geological Society in June (May 21st, 1890?), and published in 

 the September Number of the Geological Magazine. I applied to 

 Dr. Irving for particulars, and he informed me " that the argument 

 from the raised beaches and the reference to the crag at Lenham 

 •were the points referred to." 



Now, Sir, as to the argument from the raised beaches, mine is 

 quite a different argument from that used by Dr. Irving. I use it 

 in the course of a criticism on Sir A. Eamsay's diagram (Geol. and 

 Geog. of Gt. Brit. 1878, p. 343, fig. 73) as a local and recent 

 example of elevation turning a horizontal beach-line into a curve. 

 Dr. Irving omits the fall to the west, and uses it to prove western 

 elevation of the Wealden area. 



As to the Lenham beds, I have the right to refer to them without 

 obtaininoc leave. 



