TOADY

John Skillcorn
April 1988
Last edit 28 April 2007 14:47

The following article was originally published in the April 1988 issue of Aquarist and Pondkeeper.

Living your life as I do, teaching Biology in large, comprehensive schools in the north-east of England, you never quite get accustomed to the strange things that the pupils occasionally bring you to marvel at.

I well remember, for instance, the piece of swollen, pickled appendix (Yuk!) that one pupil brought me after his appendectomy, insisting that he show the rest of the class his operation scar. Then there was the girl who brooked no refusal that I should admire her Auntie Mary's lately abstracted gall stone (double Yuk!) — I though it was a blackbird's egg until I picked it up (could that really have fitted into her gall bladder?). I'm sure that you will agree that these would take some beating for originality, but beaten they were, and only just recently, after 14 years in the profession.

A particularly bothersome third year, obviously thinking that he could get round me and perhaps make me forget about the punishment which was inevitable and imminent, asked me if I had ever seen a toad with five legs.  Well, as much as I wanted to tell him that, yes, I actually had seen millions of toads, each one of which would have put a particularly leggy centipede to shame(!), I don't tell fibs, and so I had to admit the truth. He clearly had seen such an animal, and so was one up on me and, to boot, promised to bring it in to prove his claim next lesson. His ruse had worked, the end-of-lesson buzzer went, and he scarpered before I could administer the (figurative!) deadly blow. I promptly forgot about him and the toad. Imagine my surprise when, next lesson (in spite of all I tell them about touching our amphibia), he turned up with a small container, the contents of which seemed to be making plaintive, peeping noises.

The toad was an adult male British Toad, Bufo bufo, several years old, and had four normal, full-sized limbs. However, the right forelimb was quite fully double, complete with digits, and was held at an angle towards the rear of the body. The bone structure, as shown by X-ray, was complete, and the separation of the two limbs occurred at the 'elbow', the two humerus bones until then running parallel. There were only the normal two scapulae, the right, however, had two sockets, each one locating the heads of the twin humeri. The presence of the extra limb had not encumbered the animal, which had survived in the wild for a number of years, the exact number of which must remain uncertain. It fed quite happily on wax moth larvae, crickets, mealworms and earthworms.

The toad was found by David Hepburn, who, in spite of what I said in paragraph three, is really quite a pleasant guy, and only needs the occasional poke in the eye to keep him on the straight and narrow! David was a third year pupil attending Sandhill View School in the Sunderland Education Authority of Tyne and Wear, and discovered the animal in one of two large lakes known locally as Gilly Law Lakes in the Farringdon area of Sunderland. In fact, David used to live very close to the lakes, which were used for recreation purposes by the local residents. Coarse fish were found in the larger of the two lakes, along with Common Frogs, Rana temporaria, and Smooth Newts, Triturus vulgaris. David informed me that the waters are used for spawning purposes by all of the three mentioned species of amphibian, and on the day of discovery, masses of toad and frogspawn were in evidence.

I can only guess at the cause of the extra limb, but I strongly suspect that the toad, as a tadpole at the point of front limb bud germination, was attacked and damaged, the right bud perhaps being split completely into two. As regeneration in amphibia is well documented, each portion of damaged limb bud may, perhaps, have developed into a complete front limb, hence the present example — a toad which can count up to twenty-two! Some of my pupils, on the other hand, can only count up to twenty!

Thanks are due to Radiologist Mrs. Fiona Cox and Messrs. Clark and Scott MRCVS, veterinary surgeons of Low Fell, Gateshead, for their kind assistance.