July 1 8, 1878] 



NATURE 



311 



is that I have found such varying degrees of coalescence 

 between the cartilaginous rays of the dorsal fins as may 

 go far to bridge over the differences between the two 

 orders of fins, while the close resemblance sometimes 

 presented by paired fins to azygos fins (some of the 

 ventrals being so nearly like certain dorsal and anal fins), 

 •is such that I think a conclusion in favour of their essential 

 similarity of nature cannot be successfully contested. 



As to the dorsal fin, I have found incipient coalescence 

 between the rays, in Scyllian canicula, Ginglymostonta 

 cirratum, and others, but in Notidanus cinereus I have 

 found this process carried to such a degree, that there 

 comes to be one continuous basal cartilage to the dorsal 

 margin of which the cartilaginous rays are appended. 



In Pristis and Pristiophorus I found a very interesting 

 condition which I am not aware has been described. 

 The rays in these genera repose upon solid cartilages 

 which are absolutely continuous with the subjacent axial 

 skeleton. I would suggest that the lateral pressure of the 

 saw-like rostrum must be aided in these fishes by such a 

 firm attachment of the dorsal fin cartilages to the vertebral 

 column. St. George Mivart 



{To be continued) 



A HUNTING WASP 



n^HE following interesting account of a chase between 



-*- a wasp and a spider has been forwarded to us by 



Mr. Henry Cecil, who, it may be remembered, wrote to 



Nature on the subject (vol. xvii. p. 381) : — 



The Piraeus, Athens, June 19 



Dear Sir, — Your letter of April 5, and the two numbers 

 of Nature, reached this during my absence in Thessaly, 

 which must be my apology for not having sooner replied 

 to your letter. 



Though more than thirty years have elapsed since the 

 circumstance alluded to, I perfectly remember the curious 

 chase I witnessed of a very large and powerful hunting- 

 spider by a species of wasp. 



I was sitting one summer's afternoon at an open win- 

 dow (my bed-room) looking into a garden, when I was 

 surprised to observe a large and rare species of spider 

 run across the window-sill in a crouching attitude. It 

 struck me the spider was evidently alarmed or it wojuld 

 not have so fearlessly approached me. It hastened to 

 conceal itself under the projecting edge of the window- 

 sill inside the room, and had hardly done so when a very 

 fine large hunting-wasp buzzed in at the open window and 

 flew about the room evidently in search of something. 

 Finding nothing the wasp returned to the open window 

 and settled on the window-sill, running backwards and 

 forwards as a dog does when looking or searching for 

 a lost scent. It soon alighted on the track of the poor 

 spider, and in a moment it discovered its hiding-place, 

 darted down on it, and no doubt inflicted a wound with 

 its sting. The spider rushed off again and this time 

 took refuge under the bed, trying to conceal itself under 

 the framework or planks which supported the mattress. 

 The same scene occurred here, the wasp never appeared 

 to follow the spider by sight, but ran backwards and 

 forward in large circles like a hound. The moment the 

 trail of the spider was found the wasp followed all the 

 turns it had made till it came on it again. The poor 

 spider was chased from hiding-place to hiding-place — 

 out of the bedroom across a passage and into the middle 

 of another large room, where it finally succumbed to the 

 repeated stings inflicted by the wasp. Rolling itself up 

 into a ball the wasp then took possession of its prey, and 

 after ascertaining it could make no resistance, tucked it 

 up under its very long hind legs just as a hawk or eagle 

 carry off their quarry, and was flying off to its nest, when 

 I interposed and secured both for my collection. 



Both insects were rare ones, and during the ten years 

 I collected as a field naturalist in Greece, I don't remem- 



ber ever seeing more than three or four specimens of 

 either that species of wasp or spider. 



The wasp was a hunting one (a female) about an inch 

 and-a-half long, a very finely formed insect, Avhich for 

 gracefulness of form and beauty of colouring is entitled 

 to be placed at the head of its species. The legs of this 

 kind of wasp are very long and of a dark chocolate 

 brown. It runs very quickly. The wings are a light- 

 brown with dark-brown tips and long and powerful, and 

 the body beautifully mottled with pale yellow and brown. 

 It has very long fine antennae. It is not an English 

 species, but probably exists in Spain, the south df 

 France, and Italy. 



The spider, too, was a rare one. One of the largest 

 Greek hunting-spiders, nearly as large in the spread of 

 its legs as the flesh-coloured tarantula though without his 

 powerful crab-like pincers. The one I allude to must 

 have covered at least three inches in circumference when 

 its legs were fully extended. It was of a dull mottled 

 brown colour on the upper surface of the body. Very 

 difficult to distinguish from the ground. The lower part 

 of its body was, however, brilliantly coloured, the long 

 legs, or arms, being marked underneath with velvet-like 

 looking black and white rings. The head, thorax, and 

 abdomen were of a velvety black, the lower portion of 

 the latter surrounded with a bright orange ring. 



There is only one error in the account given by you in 

 Nature, that is, that you were under the impression I 

 told you, that kind of spider was the common prey of 

 that species of wasp. You must have misunderstood me. 



1. I do not think that particular kind of spider is 

 sufficiently common for this to be the case. 



2. I never saw a similar conflict of the kind before or 

 after, which as it was in a room, and not in the grass, 

 where I presume such encounters usually take place, I 

 observed under exceptionally favourable circumstances. 



I am certain the spider left no web or thread behind it. 

 I cannot be sure, how;^ver, that, as it had evidently been 

 attacked by the wasp before entering my room, a small 

 quantity of liquid may not have exuded from its wounds, 

 which may have helped the wasp in tracking it, I have 

 no doubt myself that insects have the sense of smell, and 

 probably much more developed than our own. No one, as 

 you remark, who has sugared for moths, or seen the large 

 sphingidas hovering over the strongest scented flower 

 at night, or employed a caged female moth as a lure to 

 her male admirers, can, I think, doubt this. If so, let 

 them put a saucerful of honey in a corner of a room 

 opening into a garden, throw open the window, and see 

 how soon the bees, wasps, &c., will be attracted to the 

 honey. 



There is a tradition in the east that one of the tests by 

 which the Queen of Sheba tried to prove the wisdom of 

 Solomon, was placing on a table before him two bouquets, 

 one of artificial, and the other of natural flowers, and 

 requiring that he should say which were the real and 

 which the artificial, without moving from his throne. 

 Solomon ordered the windows to be thrown open, and in 

 flew the bees, &c., which went at once to the real flowers. 



Whether the senses of insects, birds, and what we call 

 the lower creation, are similar to ours in every respect, it 

 is very difficult to say. No doubt a dog, if he could 

 speak, would say a man had not the sense of smell, and 

 would prove that his nose was worse than useless to him. 

 An eagle or hawk would say that men and moles, &c., 

 have only the rudiments of eyes, and so on. 



Man, with five very imperfectly developed senses (who 

 can say that there are not twenty senses), is the only 

 animal that is dogmatical, and denies all he cannot 

 understand. The oracle of Delphi said " Socrates was 

 the wisest man in Greece, because he was the only matt 

 who knew he knew nothing^ ' Yours faithfully, 



C. L. W. Merlin 



To Henry Cecil, Esq., Bournemouth. 



