36 
CONTRIBUTIONS TO ZOOLOGICAL PATHOLOGY. 
those engaged in the fissure, and between the layers of the fibrin- 
ous deposits, were the strongylus armatus minor — Rudolphi. Those 
that were found in the clot of blood, at the root of the mesentery, 
were the largest in size, and nearly corresponded to the size of the 
strongylus armatus major. Those in the fibrinous deposits within 
the tumour were about eight lines in length, and those engaged in 
the aperture somewhat larger. In his description of the strongylus 
armatis major, Rudolphi says, “ Strongylus infestinalis adultus 
duos circiter pollicis longus, fuscus, vasculis genitalibus albis trans- 
lucentibus, hinc variegatus; rectus ut fere strictus;” and of the 
“ strongylus minor, aliquot lineas ad poliicem usque longi, candi- 
dissimi, capite tamen (a sanguine hausto) ruberrimo, ab intestinali- 
bus specie non differunt, set! cum hisnondum adultis et decoloribus 
ex asse conveniunt*.” Those observed in this case, though of a 
larger size than those described by Rudolphi, nevertheless, in all 
other respects, they were perfectly analogous. 
Rayer, as already mentioned, has published a valuable paper 
on this form of aneurism, “ Recherches Critiques, et nouvelles 
Observations sur l’Aneurysme Vermineux et sur la Strongylus 
Armatus Minor,” in the Archives de Medecine Comparte, No. 1, 
1842, an abstract of which is contained in the valuable and useful 
publication of the Ray Society for the present year : — - 
“According to his investigations, the worm-aneurism almost 
always develops itself, in solidungulous animals, in the arteria me- 
senterica anterior, and, generally, in adult and old individuals. He 
found the cavities of the aneurismal dilatations sometimes narrowed, 
or quite filled up, by a growth of fibrous layers: in the smaller 
depositions of these layers only few strongyli were present, but in 
those of larger size they were found in greater numbers ; they 
were often also met with in the ossified walls of the aneurism. 
Raver has never seen the internal arterial coat of such worm- 
aneurisms perforated or ulcerated: the worms remain between 
the fibrous deposition, but never between the coats of the artery . 
Worm-aneurisms, it is believed, never burst, as they are always 
accompanied by hypertrophy of the arterial walls. Rayer how- 
ever, in opposition to this opinion, asserts that the strongyli pierce 
the walls of the arteries, and so get into the cavities. The most 
of the strongyli are found in the fibrous deposits, and project 
sometimes with the head, and sometimes with the tail; only a few 
lie free in the aneurismal cavities. Gruby relates a case of aneu- 
rism of the coeliac axis in the horse, in the cavity of which fibrous 
deposits and entozoa, resembling ascarides, were found. They 
* Rudolphi Entozoorum, sive Verm, In test., vol. ii, part 1, pp. 206, 207. 
