154 SVEN LOVÉK, OX THE ECHINOIBEA BESCRIBED BY LINN/EUS. 



angvistioiibus longitudinalibus . And just as iu virtue of the 

 former phrase alone tradition was led to recoguise the E. ma- 

 millatus, thus bv tlie two last Avords it has been cruided to 



*■' ^ 



select, as tbe type Linx.eus liad in view, the species widely 

 distributed in the Atlantic within the tropics from Florida 

 and the Cape Verde Islands to St Helena, and of old very 

 common in collections, which furnished Seba with his orisri- 

 nåls from the island of St. Thomas on the west coast of Africa, 

 was recoo-nised bv Leske, and was at last established bv LtiT- 

 KEN imder the Linnean name. And this was doubtless cor- 

 rect. The collection from Drottningholm contains of the genus 

 Echinometra only two specimens, both of which bclong to 

 this well-known West Indian form, described bv authors un- 

 der various names, bv Linn.eus as E. Lucunter. One of them 

 is of the common varietv, the other of the broader one, and like 

 the Heliocidaris mexicana Agass. 



The M. L. U. has no description of this species. My 

 reasons for transferring to it the description given there under 

 the E. mamillatus. have been the following'. 



When iu 1752 Linn.eus described the Echinoids then 

 present in the Queen's Museiim, he had only verv exceptionally 

 begun to apply the binary nomenclature foreshadowed in the 

 Philosophia Botanica, and there is no trace of it in the Lec- 

 tures on the o-enus Echinus delivered shortlv afterwards. Con- 

 sequently it is scarcely probable that the words: »E. Diademati 

 simillima» can have been orisinallv written under the vnomen 

 specificum^> of the E. mamillatus. Now, before the introduc- 

 tion of the binary nomenclature, whenever it was required for 

 comparison's sake to refer to some other species, this was 

 done either by means of repeating wholly or in part its »no- 

 men specificum», or by indicating its place in the series, for 

 instance through the word: »prEecedenti». If it be remembered 

 also, that in the MS of the entomological part of the ÄI. L. 

 U. the description of an additional species is sometimes found 

 written bv Linn.«U8 on the back of a schedule alreadv inscri- 

 bed with an allied species, it seems allowable to suppose that, 

 having written down on the back of the No 9: E. mamillatus, 

 the diagnosis of the No 10: E. Lucunter, he added its descrip- 

 tion beginning with: »T. praecedenti» (i. e. Echino mamillato) »si- 

 millima \ The copyist of 1764, however, it may be further 

 supposed, in his hurry inadvertently turned the schedule, then 



