442 APPENDIX. 



" Spines are found attached to the head in many different species of the 

 entozoa ; but the existence of these curious dermal processes on the Lody 

 has been observed in only one worm of the nematoid class, the Strongylus 

 horridus, an animal found by Rudolphi in the oesophagus of the water- 

 hen. In this worm they consist of reflected booklets, and are arranged 

 in four longitudinal rows, but they are only continued for a short distance 

 along the body, and, in the representation given of them, 1 appear to be 

 single instead of occurring in clusters, as in the dactylius aculeatus. 

 Professor Owen, in speaking of these epidermic processes, which he con- 

 siders serve as prehensile instruments to retain the proboscis and the 

 worm in its position, remarks, " WRen they are spread over the surface of 

 the bodv they may have the additional function of aiding in the locomo- 

 tion of the species, analogous to the spines which arm the segments of 

 the oestrus, which passes its larva state, like any entozoon, in the interior 

 of the stomach arid intestines of a higher organized animal." 2 



Two specimens of this worm, are preserved in the Museum of 

 University College, and another in the Microscopic Cabinet of 

 the Royal College of Surgeons of England. 



As the notice of the rarer forms of Entozoa may lead to their 

 more extensive observation, I am induced to add the following 

 notice of the Splroptera hominis from Professor Owen's article 

 " Entozoa" in the ( Cyclopaedia of Anatomy and Physiology/ 



" With respect to the following parasite of the human body, the Spi- 

 roptera hominis, Rud., considerable obscurity prevails. A poor woman, 

 who is still living in the workhouse of the parish of St. Sepulchre, London, 

 has been subject, since the year 1806 (when she was twenty -four years 

 old), up to the present time, to retention of urine, accompanied with dis- 

 tress and pain indicative of disease of the bladder. The catheter has been 

 employed from time to time during this long period to draw off the urine, 

 and its application has been, and continues occasionally to be, followed by 

 the extraction and subsequent discharge of worms, or vermiform sub- 

 stances, with numerous small granular bodies. The latter are of uniform 

 size, resembling small grains of sand: those which we have examined, 

 and which were preserved in spirit, present a subglobular, or irregularly 

 flattened form ; but when recently expelled, I am assured by my friend 

 Dr. Arthur Farre, that they are perfectly spherical ; they consist of an 

 external smooth, firm, diaphanous coat, including a compact mass of 

 brown and minutely granular substance. The inner surface of the con- 

 taining capsule presents, under the microscope, a regular, beautiful, and 

 minute reticulation, produced by depressions or cells of a hexagonal form. 

 These, therefore, we regard as ova, and not as fortuitous morbid produc- 

 tions. The vermiform substances are elongated bodies of a moderately 

 firm, solid, homogeneous texture, varying in length from four to eight 

 inches ; attenuated at both extremities ; having the diameter of a line 



1 'Entozoorum Historia Naturalis,' vol. i, tab. 3, figs. 8 and 9. 



* ' Cyclopaedia of Anatomy and Physiology/ Art. Entozoa, vol. ii, p. 127. 



