312 Bashford Dean Memorial Volume 



twice as large (using lb as the standard). Here follows his description as translated from 



the original Italian: 



As seen in fig. la, the root of a tooth has two [posterior] branches; these are joined 

 for almost their whole length, but in front of the line of junction, the central spine arises, as in 

 Fig. 1, and forms with the two lateral cusps a complete tooth. The apex of each spine is com- 

 posed entirely of dentine and is transparent; the spines are flexible, fig. Ic, and the root forms 

 almost a right angle with them. We have two complete teeth, and seven more or less muti- 

 lated specimens, but all are similarly formed and recognizable. All came to me from Orciano, 

 where they seem to be very rare. I have never seen a similar tooth in a Hving creature nor in 

 pictures either of fishes or reptiles. 



Since these teeth were incidentally described and were not assigned to any named 

 shark, it is not surprising that Lawley's description was lost sight of. However, the 

 publication of Carman's articles, including figures and descriptions of the teeth of Chlamy^ 



doselachus, aroused great interest in the fish 



and its relationships to various fossil forms, 



as we have shown. Lawley's discovery was 



made generally known to English-speaking 



scientists by the publication of a short arti' 



Text-figure 30 ^le by Davis in 1887- Davis noted that 



Fossil teeth of Chlamydosdachus lawleyx from the ^awley knew of no Hving or fossil form hav- 



Pliocene of Orciano, Tuscany, Italy. . ... ^i n ^ i /ta • \ rr- j 



, . , , . , r , , ,■ ing similar teeth, out he (Davis) arrirmed 



1 and lb teeth viewed from above; la from below; Ic in ° ^ 



lateral view. Note the lack of secondary cusps, (lb, nat. size; that, when these teeth are Compared with 

 all others X 2). ^]^q teeth of the frilled shark from Japan 



After Lawiey, 1876. ^^^^ Madeiran specimen of 1889 had not 



yet been captured), it may clearly be seen that they carry the same generic characters, 

 regardless of the fact that the fossil teeth are twice as large as the teeth of the present-day 

 form. Hence he proposed for this fossil form the name Chlamydoselachus lawleyi, in com- 

 memoration of Lawley's discovery. 



Comparison of the teeth in Lawley's plate (Text-figure 30) with Carman's drawing 

 (Text-figure 10), whether looked at from the front, side or below, shows plainly that these 

 teeth are congeneric. The whole general conformation is the same, even to the depressions 

 hollowed out under the anterior bases of the roots. The cusps of the teeth of C. lawleyi, 

 if correctly drawn, are slenderer than those of C. anguineus, and are slightly bulbous at the 

 base. Again the posterior parts of the base are not so long, slender and pointed as are 

 these parts in the modern form. However, these differences are trifling, and may be due 

 in part to imperfections or to changes inherent in the process of fossilization. The thing 

 which is of specific value is the absence, from the spaces between the cusps of C. lawleyi, 

 of the rudimentary or secondary cusps found in C. anguineus. Differences of size between 

 the teeth of C. lawleyi and those of C. anguineus will now be considered. 



Davis (1887) stated that the teeth of C. lawleyi are twice as long as those of C. 

 anguineus. To this we cannot agree. The teeth in Lawley's figure lb (our Text-figure 30) 

 are said in his text to be "grand, nat." The central cusp measures 7-5 mm. exactly. The 



