128 DR. T. S. COBBOLD ON NEW OR RARE ENTOZOA. [Feb. 3j 



very well with Bremser's figure of the same part. The arcuate 

 spicules, however, are not so sharp at their tips as his illustration 

 implies, and they are certainly more uniform in thickness. Dujardin 

 remarks that Rudolphi has represented the spicules as being straight, 

 whereas he himself always found them curved. Rudolphi, however, 

 was scarcely in error, since I have repeatedly noticed that these 

 arcuate organs are very nearly straight in their perfectly retracted 

 condition. Like Dujardin (and without having previously consulted 

 his description), I was particularly struck with the appearances 

 presented by certain large perivisceral corpuscles, the presence of 

 which originally suggested the specific name of the worm. Dujardin 

 very appropriately calls them corpuscules orbiculaires diaphanes, 

 but compares them, somewhat unfortunately, to little acephalocysts. 

 These bodies, as he says, are many times larger than the ova. For 

 my own part, I believe they are nutritive in character, and, like the 

 fluid in which they float, are, I suspect, chemically comparable to the 

 juice of flesh. At all events, Dr. Marcet has proved that the peri- 

 visceral fluid of the large lumbricoid worm of the horse (Ascaris 

 megalocephala) partakes of this character ; and it is no uncommon 

 thing to notice similar corpuscles in the bodies of other nematode 

 worms. Dujardin himself refers to similar bodies in an Ascaris from 

 the Perroquet. I have purposely represented a few of the eggs along 

 with the nutritive corpuscles, side by side, in order to show their 

 relative sizes (fig. 10). 



Notwithstanding the facts thus set forth in connexion with the 

 parasitic epidemic affecting the Antwerp Smerles, the entozoa in 

 question do not appear to be very common. Dujardin has remarked 

 that Heister, at Rostok, and Gebauer, at Breslau, found this parasite 

 abundant at the beginning of the 18th century; but, according to 

 examinations conducted at Vienna, the worm was found in the 

 Common Pigeon in only 1 1 instances out of 245, and thrice only in 

 38 examples of the Ring-Dove ; moreover the examination of 87 

 other pigeons and doves of different species yielded entirely negative 

 results. These data are of high practical interest, and they serve to 

 throw light upon questions of epidemiology. I may add that the 

 Dublin helminthologist, Bellingham, long ago noticed the occurrence 

 of this parasite in Ireland. 



EXPLANATION OF PLATE XVIII. 



Fig. 1 . Filaria gracilis : male, nat. size. 



2. The same : head and neck, enlarged 40 diam. 



3. The same : tail, mag. 70 diam. 



4. The same : spermatozoa, mag. 350 diam. 



5. Spiroptera turgida : nat. size. 



6. Ascaris cuspidata : tail, enlarged. 



7. Ascaris maculosa : egg, mag. 330 diam. 



8. The same: head of female, mag. 20 diam. 



9. The same : tail of male, mag. 35 diam. 



■ 10. The same : eggs and nutritive corpuscles, enlarged. 



