BOTANICAL EXCURSION. 99 



ance in this matter, and my own knowledge is limited to a few of the 

 more striking of the Lepidoptera. 



The Purple Emperor is fairly abundant, and though the date of the 

 excursion is too early for the mature insect, I have known several 

 instances of its having been secured in the larval state about that time. 

 The Purple Hairstreak is also pretty common, and the Marbled White is 

 in some seasons abundant. Among the rarer varieties which may be met 

 with at the time of the excursion, are the small Fritillary, Melitaea selene, 

 and the Skipper, Thymele alveolus. 



CUKIOUS INSTANCES OF PARASITISM IN THE TOAD. 



BY T. SPENCER COBBOLD, M.D., F.R.S., PRESIDENT OF THE 

 QUEKETT MICROSCOPICAL SOCIETY. 



Just forty years ago I remember, as a lad, to have been painfully 

 struck with the distress of a toad, as shown by its outstretched 

 fore limbs firmly planted in the soil, and by an otherwise peculiar atti- 

 tude. The victim was in a plantation of my father's rectory grounds, 

 Wortham, Suffolk. Noticing the constant outward and inward move- 

 ment of several parasites which occupied the cavity of the nose, my chief 

 thought was how I could best put the unfortunate batrachian out of its 

 misery. I killed the toad ; but the parasites were neither removed nor 

 preserved. It was, in fact, my earliest observation in helminthology. 

 From that time onward the circumstance continually recurred to me 

 as one worthy of scientific notice ; but as, until recently, I had 

 received no confh-mation of the correctness of the observation, the 

 matter was allowed to pass. During my prolonged absence from town 

 last autumn, a letter arrived from Dr. C. A. McMunn, of Clarence 

 House, Waterloo Road, near Wolverhampton, describing something very 

 similar. Writing on the 6th of August, 1879, Dr. McMunn records 

 the following incident : — " As I was returning home from the country 

 yesterday I noticed a toad slowly crawling across the road, and on taking 

 it up I found two holes in the front of its head, evidently the nostrils, 

 very much increased in size. They were filled with moving bodies. 

 To-day the animal died. The two holes have coalesced into one, and the 

 cavity formed by this coalescence is filled with the same parasites I saw 

 yesterday. I enclose the toad, as I know you are interested in such 

 matters." 



For the reasons above particularised, it was not until the expiration 

 of three months that I had opportunity to read Dr. McMunn's letter and 

 to open the paper-box containing the toad. After explaining this by 



* Communicated to the meeting of the Entomological Club held at Dr. E. H . 

 Vinen's house, Bayswater, on the 17th of Harca, 1B80. 



