142 Corres^yondence — Fossil Beads. 



tubes, some of which extend quite through, so that the specimen 

 becomes a natural bead, whilst others reach only to the central portion 

 of the fossil or beyond to near the opposite side, but without passing 

 through it completely [see 1, Fig. 1]. The tubes generally pass 

 straight through the centres of the rounded forms, but they are not 

 definitely orientated in the cushion- or pear-shaped fossils tlirough 

 which they extend either longitudinally, transversely or obliquely. 

 Out of 1799 specimens of P. globularis . . . 321 or about 18 per 

 cent were perforated; 147 being completely perforated, or natural 

 beads, whilst 174 were partially perforated. Of P. niiciformis there 

 were tubes in 32, 6 of which extended through, whilst 26 only 

 reached to varying depths in the fossils." 



In a letter just received from Dr. Hinde, the writer says : "I do 

 not doubt in the least that the perforations are natural and I think it 

 is a mistake to suppose that they have been artificially produced, 

 j^umbers of specimens from the surface soil of my garden still have 

 the holes solidly infilled with chalk and I have had to pick out the 

 material with a needle, so that in these examples, at least, the holes 

 were present when the fossil was imbedded in the chalk ooze of the 

 sea-bottom." 



He adds: "Mr. G. Crick gave me, some years ago, numerous 

 specimens of P. globularis from the Bedfordshire gravels, in which 

 they are so common as to serve as playthings for children ! These 

 gravel-specimens have their lioles wider and larger as a rule than 

 those obtained direct from the Chalk" — having been waterworn. 

 " I quite agree with you that there is no definite evidence that they 

 were used as beads by prehistoric man, although they might have 

 been so used." 



Referring to the abundance, origin, and wide distribution of this 

 little sponge in the river-valley gravels of the Ouse, Mr. Horace B. 

 Woodward, F.R.S., writes me: "The Porosphmra may well have 

 come from the Chalk of Bedfordshire, which rises up in the Dunstable 

 and Luton Downs — a continuation of the Chiltern Hills. It ma}' 

 also quite possibly have come indirectly by way of the ' Chalky 

 Boulder-clay', which covers large tracts of the Bedford Vale resting 

 on Oxford Clay, bordering the Valley Giavels. The gravel is largely 

 made up of chalk-flints, but it also contains a good deal of Oolitic 

 limestone, derived from the Great Oolite, etc., or from the 

 Boulder-clay." 



From the foregoing observations I think we may conclude — 



1. That the cylindrical perforations, so commonly present in 

 specimens of Porosphcera, are natural, not artificial, being met with as 

 frequently in specimens obtained directly from the Chalk as in those 

 met with in the Vallej^ Gravel. 



2. That their great abundance, scattered promiscuously through the 

 gravel of Bedfordshire and elsewhere, affords no evidence in favour of 

 their having been adopted as ornaments by prehistoric man. 



3. That there is no case known or recorded in which they have 

 been so used. 



On the other hand, the shells of Nassa 7ieritea and teeth of stag 

 bored for suspension probably as a head-dress or necklace were found 



