342 G. E. BODKIN AND L. D. CLEARE. 



after comparing with specimens in the British Museum, as Schistocerca vicaria, 

 Walk. Specimens were also submitted to the United States National Museum 

 and identified as being Schistocerca americana, Drury. Further specimens were then 

 submitted to the Imperial Bureau of Entomology and I cannot do better than 

 quote the Director's remarks in a letter dated 14th March 1918. " The remaining 

 locusts appear to me to be all one species and the darker forms agree absolutely 

 with S. piceifrons, Walk. ... It seems to me probable that the type of S. vicaria, 

 Walk., is merely a pale form of this species. It is possible that S. piceifrons is 

 nothing more than a northern representative of S. paranensis, but it presents some 

 constant differences in the markings and puncturation of the thorax." 



This unsatisfactory condition of affairs is well summed up by the Director of 

 the Imperial Bureau of Entomology in a later letter to the senior author dated 

 27th June 1918. He says : "I am afraid the nomenclature of the species of 

 Schistocerca is at present in a hopeless state. In the first place, it is extremely 

 difficult to know what really are specific characters in this genus, and in the second 

 place the types of the older species have not been re-examined by recent workers, 

 and, owing to the inadequacy of the descriptions, different species have in many 

 cases been assigned to the older names. Until someone revises the genus properly, 

 I am afraid the confusion will persist." 



Previous Locust Infestations. 



Official records indicate that Schistocerca sp. has visited British Guiana before, 

 and there is an undoubted specimen of this species in the British Guiana Museum 

 which was preserved from this earlier infestation. 



In August 1886 a vast swarm visited the County of Berbice and created havoc 

 among the various crops. Large sums of money were expended by the Government 

 in the destruction of the progeny of this swarm. 



From evidence that I gathered from some of the oldest inhabitants in the North 

 West District — Indians and others — it became clear that a big swarm of locusts 

 descended on that locality about the year 1886 and defoliated large areas. In 

 those days there was very little agriculture in the North West, but the Indian 

 cassava fields were destroyed. The locusts also appeared in the Pomeroon. These 

 old inhabitants were unanimous in the opinion that the species of locust of 1886 

 was the same as in 1917. 



Whether the swarm that invaded the North West in 1886 was responsible for the 

 swarm in Berbice, or whether the Berbice locusts were a separate swarm which 

 came from Venezuela at the same time, it is impossible to tell. It seems likely, 

 however, that as no destruction of the locusts in the North West was undertaken 

 they bred without hindrance and produced a further swarm which flew to Berbice. 



The following extract from a report by Mr. A. L. Layton, District Commissary 

 in Berbice, dated New Amsterdam, September 1886, is of extreme interest, as the 

 description which he gives of the immature stages of that species of locust strongly 

 coincides with similar stages of the 1917 locusts. 



"I crossed over to De Resolutie and walked about and found a great deal of corn 

 and cassava destroyed. These two vegetables they seem to prefer to anything 



