220 



HARDWICKE'S SCIENCE-GOSSIP. 



was at that time as large and complete externally as 

 it was when taken at the later date. It was nearly 

 two inches in diameter and rounded ; and was 

 suspended from the roof of the cavity by a rather 

 arge clot of earth, around which the upper part of 

 the nest had been built, the clot itself being held 

 together with and suspended from the roof of the 

 cavity by fibrous roots. The walls of the nest were 

 regular enough outside, but were very irregular 

 within ; and there was only one little circular empty 

 cell at the apex of a broad and irregular pillar 

 depending from the top of the shell. The hole of 

 entrance and exit was near the bottom on the inner 

 side of the nest, which contained a solitary worker- 

 wasp, nor were there any others in the cavity or 

 near by, this solitary individual appearing to be the 

 last of its tribe. 



CHATS ABOUT ROTIFERS. 



No. IV. 



(Synch.-eta longipes.) 



THE coronal head is very much rounded, bearing 

 four small protuberances, and two bristles or 

 styles, which doubtless act as feelers. 



The organs of locomotion are two large auricles, 

 one on each side, fringed with powerful vibratile 

 cilia," which propel the creature with marvellous 



Fig. 12:-. — Synchceta longipes. 



speed and power, which may be judged from the 

 fact that it can carry in its mouth, with the greatest 

 ease, a rotiferon quite as large as itself, and without 

 any apparent diminution of its speed. 



The body below the auricles, seen from the front, 

 is of a globose form, and terminating with a long 



foot. There is a swell on the foot between the 

 trunk and the toes, which imparts to the foot a 

 rhomboid shape. 



The 6". longipes may be readily distinguished from 

 any of the other five species of the same genus, by 

 the fact of its being furnished with only two styles 

 (the others having four or more), as well as by the 

 outline and length of the foot. 



I found this S. longipes in large numbers in a pond 

 at Emock wood, near Dundee, Forfarshire, July, 

 1886. I sent phials of different sizes filled with the 

 water to Mr. P. II. Gosse ; but it proved a bad 

 traveller, as very few specimens reached him alive, 

 and none in a healthy condition. Mr. Gosse gave it 

 the specific name of " Longipes" (as it possesses 

 a longer foot than any other known species of 

 Synchceta), and has given a short description of it 

 in a paper that appeared in the Journal of the Royal 

 Microscopical Society, February, 1887. It deposits 

 its eggs among the debris at the bottom of the pond. 

 A newly-hatched individual differs from the adult in 

 the shape of its body. Its trunk, from the auricles 

 to the foot, is conical ; but it gradually assumes the 

 round outline of the adult in a few hours, and 

 doubtless Mr. Gosse's figure of it had been drawn 

 from a young specimen. 



Its bright red eye is conspicuous in the region of 

 the mastax. The mastax is high up and near the 

 mouth, and furnished with a pair of strong forcep- 



Fig. 121. — Young of S. longipes. 



shaped jaws, which are driven out at lightning-speed 

 to catch its prey. It is the most voracious rotiferon 

 I have met with. Its food consists entirely of rotifers, 

 and it will frequently attack and devour a rotiferon 

 larger than itself. But it has a decided preference 

 for the Polyarthra platypetra, which were numerous in 

 the same water. 



It invariably seizes its prey by the head with its 

 powerful forcep jaws, never resting to enjoy a meal, 

 but continuing to swim with it in its mouth, at the 

 same time sucking the internal juices, and then 

 dropping the empty lorica to seize another victim, 

 which is often the first polyarthra it meets. The 



