In 'The Sign of the Spider', Bertram Mitford weaves a compelling narrative of escape and the unexpected consequences that ensue. Laurence Stanninghame's odyssey is articulated with a fine blend of adventure and psychological horror, revealing the perils that lie within both the human psyche and the unknown African wilderness. Mitford's writing is characteristic of late 19th-century British adventure fiction, filled with colonial sensibilities and a fascination with the exotic and dangerous landscapes. The story, in both its form and content, is also reflective of the widespread British imperialist literature of its time, which often romanticizes the protagonist's encounter with 'otherness' in distant lands.

In the literary genesis of Bertram Mitford, a contemporary of H. Rider Haggard, lies the intertwined relationship between his personal experiences and the cultural zeitgeist of imperial Britain. Mitford's own travels and services in South Africa inevitably provided him with the rich and nuanced understanding of the land's geography and societal complexities. These experiences are meticulously channeled into his depiction of Stanninghame's daunting trials, eloquently capturing the allure and danger of the colonial adventure.

Readers looking for a mixture of escapism, suspense, and a trek through historical landscapes will find 'The Sign of the Spider' to be a gratifying read. With Mitford's eloquent prose and the psychologically profound journey of its protagonist, this novel promises not just the thrill of adventure but also reflects on the consequences of the choices we make. It's an early gem in the genre that not only entertains but also provides commentary on the human condition amidst the unforgiving clutches of nature and fate.