352 DR. T. S. COBBOLD, FURTHER OBSERVATIONS ON ENTOZOA. 



only ten months old, I introduced nine living Pentastomes, and in tlie second — an old dog 

 — five examples. All the worms quickly disappeared, and I therefore fully expected a 

 satisfactory result. I was doomed to disappointment. On the 4th of March the young 

 animal was destroyed, and I made a most careful dissection of the head, without, how- 

 ever, finding a single Pentastome in any of the nasal, frontal or facial cavities. I regret 

 to add, that the old dog was subsequently killed and thrown away during my absence, 

 and I have not since had an opportunity of repeating the experiment. Prof. Leuckart, 

 having seen the memorandum above-mentioned, suggests that the parasites may have 

 been dislodged by the dog's sneezing. 



3. Trichocephalus affinis, Eudolphi. 



7". c^BW, Rudolphi ; Miram ; Lamarck; Gurlt ; Mayer; Dujardin ; Diesing, Helminth, vol. ii. p. 296 ; 



Kiichenmeister, Parasiten, p. 2/5. 

 T. Cameli, Rudolphi. 

 T. ovis, Abildgaard. 

 T. Giraff(B, Clot-Bey (non descript.), in Bulletin Scient. de TAcad. Imp. de St. Petersb. 1839, torn. vi. 



p. 94 ; also in Isis, 1839, p. 663 ; Diesing, Syst. Helminth, vol. ii. p. 294 (species inquirenda?) . 

 T. gracilis, Cobbold, Proceed. Zool. Soc. for 1860, p. 103 (non descript.). 



Remarks. — In a paper, entitled " Contributions to the Anatomy of the Giraffe," which 

 I had the honour of communicating to the Zoological Society on the 14th of February 

 last, the circumstance of my having detected Trichocepliuli in the caecum and colon of that 

 ruminant is already mentioned. At the time referred to, I purposely abstained from 

 giving any particular account of the worm, but, believing it to be a distinct form, I 

 recognized it provisionally under the title of T. gracilis. Subsequently, finding the 

 latter title to be applicable to a Triclwcephahis discovered by Olfers and Natterer in two 

 species of Agouti, I abandoned it ; and I have, moreover, since satisfied myself by a very 

 careful investigation, that the species in question is identical with the T. affinis of Eu- 

 dolphi. Under the synonym of Trichocephalus Giraffes, Diesing has grouped this worm 

 among his doubtful forms, its presence having been previously noticed by Clot-Bey in 

 the small intestines of a giraffe dissected at Cairo in the year 1839. 



Viewed with the naked eye (fig. 7), one can scarcely detect any difference between this 

 form and the well-known T. clispar of the human subject— an observation which applies 

 to some other species of the same genus. In my examples the females measure from 

 l|-2 inches in length, over all ; the males reaching from 2-2^ inches. With the pocket 

 lens, the surface of the worm appears smooth throughout, but when highly magnified, 

 peculiar markings are seen on the anterior thin portion, which probaljly also extend over 

 the body proper. The so-called neck presents a tolerably uniform thickness along its 

 entire course ; it is so narrow as to measure only from rir-ii o^h of an inch transversely, 

 whilst the finely-pointed head itself, immediately below the mouth, has a diameter less 

 than TOToth of an inch. In the fresh state the head appeared to be lobed, or rather, 

 I may say, fiu-nished with two alseform lobed appendages, as represented in fig, 8 ; but in 

 preserved specimens these appearances either partially or entirely disappear, leaving one 

 in doubt as to their true, nature. Kiichenmeister has noticed the evanescence of appa- 



