Miscellaneous. 69 



so much to enjoy, that there may be no mistake, I enclose the shell 

 of a wilk (a small specimen of Littorina littorea) which I gave it 

 two days ago, and which was today rejected in the empty state it 

 now is. 



" It is most interesting to watch the animal's movements ; every 

 day it appears in a different form, and developes new beauties. I 

 almost think it is getting tame, for it does not now shrink from ob- 

 servation as it did at first, and readily clutches upon its food. When 

 more than one wilk is given to it, it retains, by means of its feelers, 

 those it cannot at once consume, — thus making them wait their 

 turn, which comes so soon as the first taken are rejected. I once 

 saw four or five wilks, of the size of the shell now sent, in its stomach 

 at one time." — George Johnston. 



On the Organization and Development of Linguatula (Pentastoma, 

 Rudd.), accompanied with the description of a new species from the 

 Abdominal Cavity of the Mandrill. By P. J. Van Beneden. 



Among the intestinal worms, the order of the Acanthotheci is one 

 of those which most requires further anatomical and physiological 

 investigation*. I am happy to be able to fill up some of the principal 

 gaps in their natural history. 



I found in a Mandrill (Cynocephalus Mormon^, in some cysts 

 formed by the peritoneum, several Linguatulce or Pentastom<e, very 

 remarkable from their singular form. This is the first African animal 

 in which Linguatulce have been observed. The species is totally 

 different from all hitherto known, and I have called it Linguatula 

 Diesingii, in honour of the celebrated helminthologist of Vienna, 

 M. Diesing. 



This species has a white cylindrical annulated body, obtuse at both 

 extremities and as broad in front as behind ; there is considerable 

 space between the rings, of which there are only twenty ; they sud- 

 denly cease posteriorly. The mouth is rounded and situated on the 

 same line as the four hooks ; the body is fifteen millimetres in length 

 and two millimetres in breadth. 



I found several specimens of the Linguatula proboscidea in a Boa ; 

 they were fortunately alive, which enabled me to submit all their 

 parts to a microscopic examination, and I have been enabled to 

 decide the following points : — 



1. These worms have the sexes separate, contrary to the opinion 



* M. Valenciennes, in the beautiful report made to the French Academy 

 of Sciences on M. Blanchard's Memoir on the Organization of Worms, 

 stated, — " It should not be forgotten that the minute and delicate anatomy 

 of these animals can be made only on perfectly fresh individuals. One of 

 the most important genera to examine is Linguatula. I will just mention 

 to the Academy, to show how much the meeting with certain intestinal 

 worms is due to chance, that the only specimens of this very rare genus 

 deposited in the rich collection of the Museum d'Histoire Naturelle, were 

 presented by M. Dumeril, who extracted them from a tumour of the nose 

 of a dog more than thirty years ago ; and that notwithstanding the most 

 assiduous researches, no other specimens have again been met with in Paris." 

 — Camples Rendus, June 14, 1847. 



