204 



HARDWICKE'S SCIENCE-GOSSIP. 



29.97 m - to 29.47 m - The mean temperature of the 

 air, 60.2, was 2.5 below the average in the correspond- 

 ing weeks of the 20 years ending 1868. Rain fell 

 on two days of the week, to the aggregate amount 

 of 0.15 of an inch. The duration of registered bright 

 sunshine was 31.0 hours, against 31. 1 hours at Glynde 

 Place, Lewes. 



At the Royal Observatory, Greenwich, the mean 

 reading of the barometer for the week ending 14th 

 August was 29.69 in. ; and the variation was from 

 29.90 in. to 29.35 m - The mean temperature of the 

 air, 61.0, was 1.7 below the average in the corre- 

 sponding weeks of the 20 years ending 1868. Rain 

 fell on five days of the week, to the aggregate amount 

 of 0.67 of an inch. The duration of registered bright 

 sunshine in the week was 27.3 hours, against 28.5 

 hours at Glynde Place, Lewes. 



In September the average mean temperature for 

 Newcastle is 55 , for York 66°, for Liverpool 57 , 

 for London 58 , and for the South Coast 59 . 



The average rainfall for places east of Oxford from 

 Hull to Beachy Head is 2 inches ; for inland places 

 west of Oxford, it is 3 inches, and on the West 

 coast it is from 4 inches to 5 inches. 



OUR BRITISH SAW-FLIES (SIRICID.E). 

 By Joseph Anderson, junior. 



THE Siricidae are very interesting insects, be- 

 longing to the order Hymenoptera, which 

 includes the bees, wasps, ants, saw-flies, etc. ; the 

 Siricidae being a family placed in the division of 

 Hymenoptera with ovipositors, the females possess- 

 ing an organ (sometimes, as in the Sirices, of 

 considerable length) which is horny, and sufficiently 

 rigid to penetrate the bark and wood of trees, in 

 which by its means the eggs are laid. 



One species, Sirex gigas, with its orange-and- 

 black banded body, is so well known that any 

 description is unnecessary ; but, judging from the 

 scanty records of its occurrence in the entomological 

 magazines, a closely allied species, Sirex juvencits, is 

 a rarity in Britain. It may be well, therefore, to 

 record the capture of two specimens almost simultane- 

 ously in Bognor and Chichester. The first was taken 

 on September 27th, in the Vicarage, and is now in 

 the possession of Alfred Lloyd, Esq., F.E.S., etc. 

 The Chichester insect was captured in the house 

 of Dr. Arthur E. Buckell a few days earlier, being 

 secured by Mrs. Buckell in her bedroom, by whom 

 it was kindly presented to me. It was the first time 

 that I have ever had the pleasure of seeing the 

 insect alive. Both specimens are females, and my 

 own has deposited a number of snowy-white spheri- 

 cal eggs, whether fertile or not I am unable to say. 

 They present no particular appearance under the 

 microscope calling for comment. 



Juvencits differs from gigas in being of a uniform 

 shining metallic blue colour, and is somewhat 

 smaller, though the variableness in size of the 

 internal-feeding saw-flies is very remarkable. 



Curious stories illustrative of the strength of jaws 

 of the larvae, and indeed of the perfect insect too, 

 and the length of duration of the larval state are on 

 record. For instance, it seems that during the 

 Crimean War some bullets supplied to the French 

 army were found to have been riddled with holes, 

 the mischief being traced to some larvae of Sirex 

 juvencits. These had been made up in the packing- 



Fig. 1 ,0. — Sirex gigas (female). 



Fig. 131. — Sirex gigas (male). 



cases, which were of pine, from which escaping, the- 

 larvae made their way into the cartridges, gnawing 

 through them, and even eating the leaden bullets.* 



It is related by Kirby and Spence that " several 

 specimens of Sirex gigas were seen to come out of 

 the floor of a nursery in a gentleman's house, to the 

 great discomfiture both of nurse and children. The 

 story is told by Mr. Marshman on the authority of 

 Sir Joseph Banks ; and a similar circumstance, stated 

 by Mr. Ingpen, occurred in the house of a gentlemaa 

 at Henley, from the joints of the floors of which 



* Fieuier. 



