94 KEVIEW — TROPICAL MEniCINE, ETC. 



Insects— wood, dust and dirt, as has been stated. His latest description' of bed-bugs may be quoted 

 continued with advantage : — 



The fiict that tlie Leishman-Donovan body undergoes its c.xtra-corporcal development in the bed-bug, 

 Cimer rotnwi(ttus, makes it necessary to describe l)rieHy the two species of this insect associated with man. 



Accordin.i^ to Mr. Distant, tlie family C'iinkiihr, which contains four genera, ('imej', Occidcas, Oucodmnn and 

 Hemaloaijihon, belongs to the lletcroplcra, a sub-order of the h'hijiic/wla, and is placed in the series Gi/nuioccrtn. 

 between the families Phi/mafidic and (Jcrtocombida:. Mr. Distant informs rac tlie genus Cimcx at present eoutains 

 four species, ' 'inifj- Ici-lulanas, Linn., Cimcr rotimdalun, Sign., Cimc.r pipislrclli, Jenyns, and Cirnej- columbariiis, all 

 of which have the following characters : The head is short and broad with two prominent eyes, but no ocelli. 

 The antenmu arc four-jointed, the apical joints being slender; the elytra are rudimentary and lie over the 

 metathora.x. The jjrothorax is semilunar in shape with its anterior angles considerably extended. The abdomen, 

 which is uncovered, consists of seven segments and an eighth anal appendage ; the legs are slender, the anterior 

 tibiae more tlian twice as long, and the posterior three times as long, as the tarsi, which are three-jointed. The 

 proboscis is fle.Kod in a groove beneath the head and prothorax. 



Tjipe. species, i.'imej- leclularius, Linn. The adult insect of this species is reddish-brown in colour and is 

 covered with fine hairs ; it varies in length from 4-5 mm. to JJ mm., the male usually being a little smaller than 

 the female. The head is short and broad and is inserted into a notch in the protliorax ; it contains two lateral 

 prominent eyes in front of which arc the two antennae and in the median line the thick first segment of the 

 labrum which is continuous with the dorsal integument of the head. The antennae consist of four segments, tlie 

 first two being the thi<;ker, while the third and fourth are slender and covered with long hairs. 



The prothorax is semilunar in shape with two rounded horns extending close up to the eyes ; its upper surface 

 is raised in the centre and towards the sides, ending abruptly at a line a little beyond the level of the eyes; the 

 remainder of the surface, including the two horns, is flattened from aljove downwards. The ventral surface of the 

 prothora.x is concave and hollowed out on each side of the mid-line where the first pair of legs are inserted. The 

 mesothorax, as seen fi'om the dorsal surface, is triangular in shape with its apex projecting over the mesothorax and 

 between the elytra. The mesothorax, next in size to the prothorax, is almost entirely covered on its dorsal side by 

 the elytra, and on the ventral surface is .seen as a small cleft on the inner side of the middle coxa. The elytra, 

 which are inserted into the mesothorax just below the lateral angles, are two rudimentary scallop-shaped pieces 

 of chitin lying over the metathorax and sides of the first abdominal segment. Their dorsal surfaces are convex 

 and covered with bristles, while their ventral surfaces are concave. The abdomen is rounded and consists of seven 

 segments with an eighth and appendage. It is broadest at the third segment and gradually becomes narrower 

 towards the end where it is covered with long hairs. In the male, the penis is seen flexed in a notch between the 

 seventh and eighth segments. 



This bug is distributed through Europe and North America, and is also found in Suez, Egypt, the Sudan, the 

 North-West Frontier Province of India, China, South Africa and Australia. 



Cimcx rotimdatus. Sign., or the Indian bed-bug, is darker than the above species, being of deep mahogany 

 colour ; its head is not as long or as broad as that of tediilarius. Its prothorax is also narrower and shorter, is 

 more rounded and not flattened at the sides as is the prothorax of tlie type species. Its abdomen is orbicular, 

 being broadest at the second segment, and tapers more abruptly towards the end ; in all other respects it is similar 

 to Cimcx leclularius. 



Cimcx rotundaiiis is distributed throughout India, Burma, Assam, IMalay, and is also found in Aden, Sierra 

 Leone, the Islands of Mauritius, Reunion, St. Vincent and Porto Rico. 



Cimcx pipistrellli, Jenyns, is similar in colour to rotundalus, its prothorax is also less marginal, and in all 

 respects it is more closely allied to the Indian bed-bug. 



Cimcx colmnbarius, Jenyns, has a similar prothorax to leclularius and is also of the same colour. 



Dissection of Ihe bed-bug. The following method of dissecting the bed-bug has been found satisfactory. After 

 having killed the insect by placing it in a tube with a plug of cotton wool containing a few drops of chloroform, it 

 is taken up with a pair of forceps and the legs are pulled off. In removing the fore legs it is necessary to be 

 careful not to injure the prothorax, as they are firmly fixed in concavities on its under surface. The elytra are 

 next removed by raising them with a fine pair of forceps and gently twisting them off from their joints at the 

 angles of the mesothorax. The bug is now placed in a drop of normal saline solution with its head directed 

 towards the dissector. A fine needle is inserted with the left hand into the right side of the prothorax, while with 

 another fine needle in the right hand the joint between the prothorax and mesothorax is separated. By gently 

 drawing the needle in the left, hand and by exerting pressure on the dorsal surface of the abdomen with the other 

 needle, the cesophagus, midgut and the remaining part of the intestinal tract arc drawn out, and any portion can 

 then be isolated and examined. The salivary glands lying on each side of the oesophagus are also exposed by this 

 method. The ducts of the salivary glands and the oesophagus can be followed into the crop situated in the head 

 by carefully removing the prothorax. 



As the barracks in Khartoum used to swarm with bugs, and as they are troublesome in 

 the quarters of the Public Works Department, these notes may be of some interest, though 

 one has never heard of any similar condition prevailing locally. 



The endemic gastric catarrh mentioned under " Bed-bugs " is described by Kirchenberger 

 and Vala.-* It occurs during the summer months in the southern provinces of Austria- 

 Hungary, and specially attacks soldiers in barracks. The incubation period is three to five 

 days, followed by a prodromal stage of a few hours characterised by malaise, headache and 



' Patton, W. S. (1907), "The Development of the Leishman-Donovan Parasite in Cimex Rotundatus." 

 Scientific Memoirs of the Government of India, No. 31. 



= Kirchenberger and Vala (September 3rd, 1907). Allgem. Wien. Med. Zeilung. 



' Article not consulted in the original. 



