VOL. XIII.] PHILOSOPHICAL TRANSACTIONS. SQ/ 



candidi coloris fasclam referebat; but notwithstanding these authorities, I shall 

 still suspend my belief of these double heads till better information. And indeed 

 Tulpius himself seems to me to suspect the truth of the observation, having in 

 the last edition of his book left it out, without taking any notice of it, and 

 given another very different ; and in the same figure he has erased the former 

 heads, and clapped on a new one, to the old body (fig. 4, pi. IQ,) quite different 

 from what was before. But by all I can see in his figures, I cannot but think 

 he is at the wrong end ; for by considering the prominence of the joints, the 

 placing of its spots, and the difference of its ends, I should rather look for it 

 at the smallest extreme, which he makes the tail, than the other where he has 

 now placed it. 



Jo. Michael Fehr, a German Curioso, in his Treatise de Hier^ picrA sive de 

 Absinthio, in the year 1644, observed in a piece voided by a patient, about 6 

 yards long, a head miich different from that of Tulpius; he describes this 

 worm cum collo sensim angustiore, et rotnndiore in minutissimum capitulum 

 atrum, et verrucosum, trium papaveris seminum apte conjunctorum formam 

 exprimens, desinentem: cujus iconem ob raritatem hie addidimus. (fig. 5.) 

 Indeed I must confess that account I had from the women who first observed it, 

 and the patient who voided that worm I mentioned to have by me 8 yards long, 

 and was given me by my worthy friend Mr. Houghton an apothecary, seemed 

 agreeable to this; though, when I first saw it, I could observe no such thing; 

 and therefore am apt to think it was only some thrumbs of the inward coat of 

 the intestine, which might stick to the hooks here, which might make this 

 figure. For, in the heads of all I have yet had an opportunity of seeing, I 

 could never observe any such thing. 



I shall therefore now deliver my observations of the heads of this worm as I 

 have seen them, in three several ones I have taken out of the bodies of dogs 

 on dissection. One was in a dog I opened at our private meetings, at the Ana- 

 tomical Theatre of the College of Physicians, where I observed this worm alive 

 in the ileum ; not lying straight, but in many places winding and doubling. 

 Having observed how the joints were, I traced it up, by carefully opening the 

 intestine to the smallest extreme, where I expected the head to be ; and which 

 lay towards the duodenum; whereas the broader end was downward towards the 

 rectum; and this broad end was free, without adhering; whereas that smaller 

 extreme stuck so firmly, and had fastened itself to the inward coat of the intes- 

 tine, that it was not without some trouble, by gently raising it with my nail, 

 that I freed it from its adhesion. Having lifted it up, I carefully viewed it; and 

 observed neither that biceps in Tulpius's first figure, nor the head like a tricoccos 

 as in Mich. Fehr, but a very slender body; which being alive, it would some- 



